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The Effect of the 'instructional Technologies' Course on the Competencies of Teacher Candidates in Using Web 2.0 Tools: The Case of Early Childhood Education Program
No full textThis study examines teacher candidates' competencies in using Web 2.0 tools and developing digital teaching materials for early childhood education within the scope of the Instructional Technologies Course. This research study investigates the course-based efforts to improve the quality of the education of teacher candidates and to better understand specific aspects of a course aimed at developing the use of instructional technologies among early childhood teachers in T & uuml;rkiye. While the study focuses on the teacher candidates of early childhood education, investigating problems and best solutions of the pre-service teacher training to develop the digital competencies of teacher candidates are valued. The findings indicate that with guidance and motivation from the instructor, teacher candidates effectively utilize Web 2.0 tools to create digital teaching materials. The developed digital teaching materials demonstrate high instructional suitability, curriculum alignment, and technical proficiency, though improvement is needed in visual design proficiency. The Instructional Technologies course has positive effects on designing effective digital teaching materials and using new Web 2.0 tools. While the course positively impacts candidates' skills with Web 2.0 tools, its two-hour duration may limit long-term retention of these skills. The study emphasized that the mandatory curriculum of the teacher education program limited the course to two hours. Therefore, the findings suggest that the practice hours and functioning of the Instructional Technologies course in the Teacher Training Programs should be revised to support pre-service teachers' competencies in T & uuml;rkiye. The suggestions for the course include that (1) the effective execution of the process of preparing pre-service teachers' own original products, (2) experimenting with the competencies to be developed and preparing original studies, (3) determining the most appropriate evaluation criteria for the developed digital teaching materials, (4) the use of product and material evaluation, self-evaluation, peer evaluation methods in the measurement and evaluation process, (5) designing digital course materials through functional criticism.Scientific and Technological Research Council of Turkiye (TUBIdot;TAK)Open access funding provided by the Scientific and Technological Research Council of Turkiye (TUB & Idot;TAK).Emerging Sources Citation Inde
Design and Implementation of a High Power Density GaN-Based USB-PD Charger
No full textThis paper presents the design and implementation of a high-power-density GaN-based USB-PD charger capable of delivering up to 100W. Gallium Nitride (GaN) power devices offer significant advantages over traditional silicon-based components, including higher efficiency, reduced switching losses, and increased power density, making them an ideal choice for modern fast-charging applications. In this study, various power conversion topologies and commercially available GaN-based integrated circuits (ICs) are analyzed and compared to determine the most efficient and thermally optimized solution. Extensive thermal analysis is performed to evaluate the heat dissipation and efficiency of the system under full-load conditions. Experimental tests verified the charger's performance, demonstrating high efficiency and superior thermal management compared to conventional silicon-based solutions. The results highlight the potential of GaN technology in achieving compact, efficient, and high-power-density USB-PD chargers suitable for next-generation consumer electronics.Scientific and Technological Research Council of Turkey (TUBITAK) [3240308]This work is supported by The Scientific and Technological Research Council of Turkey (TUBITAK) funded project (3240308).Conference Proceedings Citation Index - Scienc
Mindfulness Temelli Arabuluculuk
No full textHukuk, insanlık tarihi boyunca adaletin sağlanmasından sorumlu bir bilim dalıdır. Ancak hukukun gerek normatif yapısı, gerekse yıllar içinde oluşmuş rekabetçi kültürü, günümüzde insanların adalet ihtiyacını tam olarak karşılamakta yetersiz kalmaktadır. Genel olarak hukuk sistemlerinde yerleşik kazan-kaybet anlayışı ile insan psikolojisini dışlayan katı yapı, sistemi bazı açılardan duyarsız kılmaktadır. Hukuk profesyonellerinin ve adalet arayışı içindeki bireylerin psikolojik strese maruz kalması, sistemin gölge yanlarını oluşturmaktadır. Bu durum, alternatif uyuşmazlık çözüm yollarına olan ilgiyi artırmış ve hukukta daha bütüncül ve duyarlı yaklaşımlara duyulan ihtiyacın fark edilmesini sağlamıştır. Bilinçli farkındalık (mindfulness) yaklaşımı, başta sağlık, psikoloji, iyi-oluş, eğitim, işyeri uygulamaları, iletişim vb. alanlarla olmak üzere, birçok alanda olumlu ve etkili sonuçlar vermektedir. Mindfulness kavramı, Doğu'nun zihni gözlemleme ve meditasyon deneyimine dayalı binlerce yıllık bilgelik geleneğinden doğmuş ve bugün Batı'nın bilimi ile harmanlanarak bilimsel bir temele oturmuştur. Bu bütüncül yaklaşım, hukuk uygulamalarında daha bilinçli, daha duyarlı ve dönüştürücü etki bırakma gücüne sahiptir. Yapılan bilimsel araştırmalar, mindfulness uygulamalarının stres yönetimi, duyguların düzenlenmesi, empati, işbirliği, etik davranış, dikkat gelişimi ve bilişsel esneklik gibi birçok konuda olumlu etkilerinin olduğunu doğrulamıştır. Bu yaklaşımın ayrıca, genel olarak hukukçular ve özellikle işbirliğine yönelik çözümleri destekleyen arabulucular açsından, oldukça faydalı sonuçlar doğurma potansiyeli bulunmaktadır. Mindfulness'ın hukuk alanına entegrasyonu, başta Amerika Birleşik Devletleri olmak üzere Avrupa'da birçok ülkede üzerinde çalışılan ve olumlu sonuçları kaydedilen bir konudur. Bu kapsamda, prestijli üniversitelerin hukuk fakültelerinde mindfulness temelli eğitim modüllerine yer vermek, hukukçulara yönelik eğitim ve seminerler düzenlemek, yapılan çalışmalar arasındadır. Ancak Türkiye'de bu konuda sınırlı çalışmalar bulunmaktadır, bu tez çalışması ile bu eksikliğin giderilmesi amaçlanmıştır.The science of Law was responsible of ensuring justice throughout human history. However, both the normative structure of the law and the competitive culture that has developed over the years are insufficient to fully meet society's need for justice today. In general, the entrenched win-lose mentality embedded in legal systems and the rigid structure that often excludes human psychology constitute the insensitive aspects of the system. The exposure of legal professionals and individuals seeking justice to psychological stress constitutes the shadow side of the system. This situation has increased the interest in alternative dispute resolution methods and has led to the recognition of the need for more holistic and sensitive approaches in legal practice. The mindfulness approach which has yielded positive and effective results in many areas, especially in health, psychology, well-being, education, workplace practices, communication, etc. also holds significant potential for transforming legal practices in a holistic sense. The concept of mindfulness, rooted in the ancient wisdom traditions of the East based on meditation and introspection, has been blended with the science of the West today. This holistic approach has the power to create greater awareness, sensitivity, and transformative impact in legal applications. Scientific research has confirmed that mindfulness practices have positive effects on many issues such as stress management, emotional regulation, empathy, cooperation, ethical awareness, attention development and cognitive flexibility. This approach also has the potential to be very beneficial for legal professionals in general and mediators who support collaborative solutions in particular. The integration of mindfulness into the field of law is a subject that has been studied in particularly in the United States and many countries in Europe, and has recorded positive results. In this context, including mindfulness-based training modules in law faculties of prestigious universities and organizing training and seminars for legal professionals are among the studies carried out. However, there are limited studies on this subject in Turkey, and this thesis aims to to address this gap in the literature
Dual Estimation of State of Charge and State of Health for Lithium Ion Batteries
No full textLityum-iyon bataryaların verimli ve güvenilir bir şekilde çalışabilmesi için Şarj Durumu (SOC) ve Sağlık Durumu (SOH) tahminlerinin doğru bir şekilde yapılması büyük önem taşımaktadır. Özellikle sanayi uygulamalarında batarya performansının izlenmesi ve kestirimci bakım stratejilerinin geliştirilmesi kritik bir gereklilik olarak öne çıkmaktadır. Endüstride yaygın olarak kullanılan sistemlerde SOC tahmini çoğunlukla Coulomb Sayımı yöntemi temel alınarak gerçekleştirilmektedir. Bu yöntem basitliği ve kolay uygulanabilirliği nedeniyle tercih edilmekte olup, geniş bir kullanım alanına sahiptir. Ancak, zaman içinde biriken hatalar, batarya yaşlanması, kapasite kaybı ve ölçüm belirsizlikleri nedeniyle doğruluk kaybına uğrayabilmektedir. Elimizde bulunan gerçek sistemde SOC tahmini, yalnızca Coulomb Sayımı ile değil, Açık Devre Gerilimi (OCV)-SOC grafiğine dayalı bir başlangıç tahmini ile desteklenen hibrit bir yöntem kullanılarak gerçekleştirilmektedir. Bu yaklaşım, hesaplama maliyeti ve doğruluk arasında pratik bir denge sunmasına rağmen, uzun vadede sapmalara ve tahmin hatalarına karşı hassasiyet göstermektedir. Bunun yanı sıra, mevcut sistemde SOH tahmini yapılmamaktadır. SOH'un belirlenememesi, batarya yaşlanma sürecinin izlenmesini ve kalan ömrün tahmin edilmesini zorlaştırmaktadır. Bu çalışmada, SOC ve SOH'un eş zamanlı olarak tahmin edilmesini sağlamak amacıyla Genişletilmiş Kalman Filtresi (EKF) tabanlı bir çiftli tahmin çerçevesi önerilmektedir. Önerilen yöntem, belirli bir deşarj senaryosu altında bir MATLAB batarya modeli kullanılarak test edilmiştir. EKF tabanlı yaklaşım, model odaklı bir tahmin stratejisi benimseyerek geleneksel yöntemlere kıyasla batarya durum tahmininin sağlamlığını ve güvenilirliğini artırmaktadır. Bu araştırma, mevcut sistemlerde kullanılan tekil tahmin yöntemlerinden çiftli tahmin çerçevesine geçişin avantajlarını ortaya koyarak, batarya yönetim sistemlerinin doğruluğunu ve adaptif izleme yeteneklerini geliştirmeyi hedeflemektedir. Çalışma sonuçları, EKF tabanlı çiftli tahmin yaklaşımının uygulanabilirliğini göstererek, sanayi uygulamalarında batarya sağlığının daha hassas bir şekilde izlenmesine ve kestirimci bakım stratejilerinin geliştirilmesine katkı sunmaktadır.Accurate estimation of the State of Charge (SOC) and State of Health (SOH) is crucial for the efficient and reliable operation of lithium-ion batteries, particularly in industrial applications where performance monitoring and predictive maintenance are essential. In most industrial systems, SOC estimation primarily relies on Coulomb Counting due to its simplicity and ease of implementation. However, this method is prone to cumulative errors over time, as it does not account for battery aging, capacity fade, and measurement inaccuracies. In real-time applications, SOC estimation is performed using a hybrid approach that combines Coulomb Counting with an Open Circuit Voltage (OCV)-SOC graph for initial estimation. This approach provides a practical trade-off between computational efficiency and accuracy, yet it remains susceptible to drift and long-term estimation errors. Additionally, our current system does not incorporate any dedicated SOH estimation methodology, which limits the ability for battery degradation and prediction its remaining useful life. To address these challenges, this study proposes a dual estimation framework utilizing the Extended Kalman Filter (EKF) to simultaneously estimate both SOC and SOH. A MATLAB-based battery model is employed to simulate a specific discharge scenario, allowing for a controlled evaluation of the proposed method. The EKF-based approach integrates a model-driven estimation strategy, which enhances the robustness and reliability of battery state estimation compared to conventional methods. By transitioning from a single estimation method to a dual estimation framework, this research aims to improve battery management systems by providing more accurate and adaptive monitoring capabilities. The findings of this study demonstrate the feasibility of implementing an EKF-based dual estimation approach, paving the way for improved battery health diagnostics and predictive maintenance strategies in real-world applications
Autoimmune Encephalitis and Musicogenic Epilepsy: a Case of Gad65 Antibody-Associated Seizure
No full textMusicogenic epilepsy (ME) is a rare form of reflex epilepsy with a prevalence of 1 in 10,000,000. Recent research suggests a potential link between ME and autoimmune encephalitis, particularly involving glutamic acid decarboxylase 65-isoform (GAD65) antibodies. A 48-year-old female presented with a one-year history of music-triggered seizures. Her episodes were characterized by an initial aura followed by unresponsiveness and oral automatisms. Electroencephalography revealed abnormalities in the left anterior temporal lobe and temporal leads. Laboratory studies showed positive anti-GAD65 antibodies. The patient was treated with a combination of antiepileptic medication (Lamotrigine) and corticosteroids and intravenous immunoglobulin. This case contributes to the growing evidence supporting an association between ME and autoimmune mechanisms, particularly GAD65 antibody-mediated autoimmunity. It highlights the importance of screening autoimmune factors in ME patients and highlights the need for further research into targeted treatment strategies.Emerging Sources Citation Inde
Sürdürülebilir Kalkınma Bağlamında Yeşil Kent için Yeşil Lojistik: Artvin/Hopa Üzerine Bir Değerlendirme
No full textDünyada lojistik sektörü, küresel ticaretin büyümesi ile birlikte hızla gelişen ve önem kazanan bir sektördür. Türkiye’de ise lojistik sektörü; ülkenin stratejik konumu, limanlarının ve havaalanlarının sahip olduğu potansiyel ile hayati önem arz etmektedir. Türkiye’nin Karadeniz kıyısında bulunan liman kenti olan Artvin’in Hopa ilçesi ise bu özelliklerinden ötürü lojistik açıdan stratejik bir konuma sahiptir. Hopa Limanı, özellikle Karadeniz’e kıyısı bulunan ülkelerle gerçekleştirilen deniz ticaretinin önemli bir merkezi konumundadır. Nitekim denizyolu ve karayolu ile ticaretin yapıldığı Hopa ilçesi, lojistik açıdan gerek bölge gerekse ülke ekonomisi için önemli bir potansiyele sahiptir. Bu çalışmanın amacı, yeşil lojistik için yeşil kentlerin oluşturulmasının önemi ve Artvin ilinin Hopa ilçesindeki sürdürülebilir kalkınma potansiyeli üzerine bir değerlendirme yapmaktır. Araştırmanın problemi ise, Artvin/Hopa’nın mevcut lojistik altyapısının çevresel etkileri ve sürdürülebilirlik açısından değerlendirilmesiyle yeşil lojistik uygulamalarının bu alanda nasıl geliştirilebileceğinin incelenmesi biçimindedir. Sonuç olarak Artvin/Hopa’nın coğrafi konumu ve doğal kaynakları bakımından yeşil lojistik stratejilerinin başarıyla uygulanabileceği bir potansiyele sahip olduğunu belirtmek mümkündür. Bu çalışmanın önemi ve literatürden farklı yanı, Artvin/Hopa için yeşil lojistik stratejilerinin oluşturulmasına katkı sağlayacak şekilde hazırlanmasıdır
Single-Phase Multilevel Inverter With a Coupled Inductor
No full textMultilevel inverters have become indispensable components in various power electronic applications, particularly in medium-and high-voltage scenarios. This paper introduces a novel single-phase seventeen-level inverter design that utilizes three DC sources and a coupled inductor, resulting in a reduced size and cost. The incorporation of coupled inductors empowers multilevel inverters to enhance performance, yielding high-quality output voltages while minimizing current stress on power devices. A topology-specific level shifted pulse-width modulation (LS-PWM) technique is presented and thoroughly discussed. The proposed topology is simulated and a hardware prototype was constructed to verify the performance of the proposed seventeen-level topology. The outcomes indicate that the implemented topology successfully attains the anticipated performance. Furthermore, a comparative analysis with other existing topologies has been conducted, unequivocally confirming the superior performance, efficiency, and cost of the proposed topology, setting it apart as an outstanding solution in the field of multilevel inverters.Science Citation Index Expande
Effect of Nanoparticle Size on the Thermal Performance of Paraffin-O2 Hybrid Heat Sink Using Molecular Dynamics Approach
No full textPhase change materials and nanostructures are necessary to raise the efficiency of thermal energy (TE) storage systems, hence improving the efficiency of energy storage units. For this reason, the construction makes use of metal oxides and nanoscale metal particles. This work examined, using molecular dynamics modeling, the influence of nanoparticle (NP) size on the paraffin/O2/Al2O3 hybrid heat sink performance. The results show that the thermal conductivity of the structure rose from 391.34 to 404.44 W/m.K as Al2O3 NP size rose. This resulted in lengthier NP aggregation from 6.95 to 7.02 ns. Moreover, changing the radius of NPs in a simulated construction would boost the heat flow from 333.99 to 368.05 W/m2. Consequently, phase change materials and nanostructures improve the heat transfer (HT) and storage capacity of the system. Renewable energy systems, electronics cooling, and thermal management in industrial processes are just a few of the many disciplines where this technology might find use.Science Citation Index Expande
The Thermal-Flow Performance of Water-Al2o3 Nanofluid Flow in an Elliptical Duct Heat Exchanger Equipped With Two Rotating Twisted Tapes
No full textBackground: The thermal-flow performance of nanofluid (NF) flow in an elliptical duct heat exchanger fitted and turbulated with two rotating tapes is investigated. The issues concerning rotating twisted tapes inside the oval tubes using NF as the working fluid simulated with two-phase modeling have received less attention in previous studies. Methods: Considering the importance of employing the heat transfer improving methods in tubular heat exchangers, the passive and ative heat transfer improving methods examined here. As a novel study case, the rotated tapes beside the water-Al2O3 NF of was used; and sensitivity analysis was performed to reveal the effect of the volume fraction of nanoparticles (ϕ), tapes rotational speed and Re number on the Nu number, pumping power and figure of merit (FOM). The heat flux of 5000 Wm−2 was applied to the wall surface, and the two-phase mixture method was employed for the simulation. The heat exchanger performance is studied in cases of fixed and rotating twisted tapes with three different rotational speeds. The results show that increasing the Re number, ϕ and the rotation speed of the blades would increase the Nu number and pumping power in all cases. The increase in ϕ improves the Nu number by 6.1 %–19.4 % and the pumping power by 59.2–280 %. The Nu number change by increasing ϕ is lower at low Re numbers and becomes higher at high Re numbers. The effect of ϕ increment on heat transfer is increasing but took place with a higher inclination rate in rotating tapes rather than stationary tapes and plain tube cases. In the cases of rotated twisted tape mode, the value of FOM is always greater than one and is below 0.9 for stationary mode. Significant findings: The highest value of FOM is 1.57, which is for the highest rotational speeds, the lowest Re number, and ϕ = 1 %. Increasing the Re number reduces the FOM while increasing ϕ improves it. Practical significance and potential area of application: The increasing need for efficient heat transfer in heat exchanger devices necessitated the application of heat transfer augmentation techniques. The effects of twisted tapes, their rotation, and the application of NFs in heat exchangers as the active and passive heat transfer increment methods are studied numerically. © 2025 The Author(s
Dentoalveolar and Skeletal Effects of an Anterior Open Bite Treatment Protocol Using Zygomatic Anchorage
No full textObjectivePrimary aim was to analyse dentoalveolar and skeletal effects induced by an anterior open bite (AOB) treatment protocol for intrusion of maxillary buccal segment. Secondary aim was to investigate whether a subsequent change occurred in hyoid position.Materials and MethodsStudy group included 28 non-growing subjects treated in academic setting for correction of AOB. All patients received same appliance that included bilateral acrylic bite-blocks covering posterior dentition. Intrusive force was applied between buccal bars of appliance and zygomatic multipurpose implants. Lateral cephalograms taken at pre-treatment (T0) and after intrusion (T1) were analysed using NemoCeph software. Eight skeletal, 9 dental, 6 soft tissue and 5 hyoid parameters were measured and evaluated statistically.ResultsMean open bite was -3.2 +/- 2.1 mm at T0. T1-T0 duration was 9.6 +/- 1.9 months. Increase in SNB (1.1 degrees +/- 2.1 degrees) and the decrease in ANB (-1.1 degrees +/- 1.3 degrees), Y-axis (-0.5 degrees +/- 3.5 degrees), SN-GoGn (-2.0 degrees +/- -2.5 degrees) and lower facial height (-1.4 +/- 2.1 mm) were significant, indicating mandibular counter-clockwise rotation. Overjet and open bite decreased significantly (-1.8 +/- 2.3 mm and 4.2 +/- 2.1 mm, respectively). Maxillary molars intruded (U6-PP: -3.1 +/- 1.3 mm) and distalised (Delta U6-TVL: -1.5 +/- 2.7 mm) significantly. Mean change in L6-MP was significant (0.9 +/- 1.4 mm) showing mandibular molar eruption. Lower lip-true vertical line (TVL) showed significant forward movement of lower lip (-1.8 +/- 2.3 mm). Mean changes in hyoid parameters were not significant.ConclusionSignificant maxillary buccal segment intrusion was achieved in a relatively short period. AOB was corrected while facial profile and smile aesthetics were improved. Distalisation of maxillary molar suggests that intrusive force vector can be modified to achieve simultaneous intrusion and distalisation.Science Citation Index Expande