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Influence of Nd2O3-doped PVA interlayer on the optoelectrical response of a photodiode
No full textThis study examines the photovoltaic properties of a Schottky photodiode (PD) based on the Au/PVA:Nd2O3/n-Si structure under various light and dark conditions. A PVA polymer layer doped with Nd2O3 is applied to the metal-semiconductor (MS) interface to form a metal-nanocomposite-semiconductor (MNS) Schottky PD. Characterization of the PVA:Nd2O3 nanocomposite is conducted using Fourier Transform Infrared (FTIR) and Attenuated Total Reflection (ATR) analyses. Key electronic properties such as reverse-saturation current (I0), ideality factor (n), series/shunt resistances (Rs/Rsh), barrier height (ΦB0), interface state density (Nss), photocurrent (Iph), photosensitivity (S), optical responsivity (R), and specific detectivity (D*) are analyzed. The nanocomposite enhances photosensitivity, responsivity, and detectivity by 1.7 × 104, 4.79 A W−1, and 1.07 × 1012 Jones, respectively. Results demonstrate that the Au/PVA:Nd2O3/n-Si structure exhibits excellent photo-response, making it a potential replacement for traditional MS-type Schottky PDs in optoelectronics and solar applications
The Effects of Different Electric Motor Stator Designs on Vibration Using Finite Element Analysis
No full textPurposeThis study investigates the influence of different stator designs, key components in electric motors, on vibration and deformation behavior through finite element analysis (FEA). The aim here is to reveal the vibration behavior of different stator designs in isolation and their effects on efficiency when integrated into the motor structure, thereby providing comparative data on the potential relationship between these two parameters and identifying the most favorable design from a structural perspective. The study presents the results arising from design variations without explicitly addressing the relationship between vibration and efficiency.MethodsThe analysis was conducted on a four-pole, 5.5 kW asynchronous (induction) motor. Vibration characteristics were evaluated across various stator tooth, slot, and duct configurations. The torque, natural frequency, and efficiency of the complete assembly, comprising different stator structures along with the rotor and shaft, were calculated. Modal analyses were then carried out to identify the natural frequencies of the stators. Based on these, harmonic response analyses were performed to assess deformation and normal stress across the 50-5000 Hz frequency range.ResultsThe findings revealed that the shape of the duct, whether rectangular or circular, had no significant effect on the natural frequency, provided that the surface area remained constant. At synchronous speed, designs with parallel teeth achieved approximately 79% efficiency, while those with tapered slots reached about 65%.ConclusionOverall, the study demonstrates that stators with parallel teeth and circular ducts undergo less deformation and offer higher efficiency compared to other design combinations. Although this situation suggests that efficiency may increase as vibration decreases, it is considered that this study provides a foundation for more detailed investigations to confirm this in future research
Komplike Kron-Kök Kırığı Olan Üst Sol Santral Dişin Multidisipliner Tedavisi: Vaka Raporu
No full textInvestigation of Electrical Behavior of Au/Ti/AlN/Si Schottky Diode via Gaussian Distribution Barrier Modeling
No full textThis study presents a comprehensive analysis of the temperature-dependent electrical behavior of Au/Ti/AlN/n-Si Schottky diode using both experimental measurements and theoretical modeling. The key diode parameters, namely the ideality factor (n) and the zero-bias barrier height (phi B0) were extracted over the temperature range of 100-400 K and were found to exhibit a strong dependence on temperature. The experimental results revealed that "phi B0" increases and "n" decreases with rising temperature, consistent with the presence of a Gaussian distribution of barrier heights and a transition toward thermionic emission-dominated transport. A theoretical model incorporating barrier inhomogeneities was employed and yielding results in close agreement with experimental trends, particularly for phi B0. Modified Richardson plots confirmed the validity of the Gaussian distribution model, allowing for accurate determination of the average barrier height and Richardson constant. While the theoretical predictions matched the experimental behavior well at high temperatures, deviations at lower temperatures showed the influence of interface states and nonideal effects. The observed behavior indicates that the charge transport mechanism is influenced by spatial variations in the potential barrier, particularly at lower temperatures
Comparative Analysis of Ad Click Behavior Prediction Using GAN-Augmented Data and Traditional Machine Learning Techniques
No full textIn e-commerce, predicting click-through rates (CTR) is crucial to anticipating user behavior. User historical data can be used to extract interests and enhance CTR prediction, leading to higher accuracy. In this study, a generative adversarial network (GAN) has been used to tackle the issue of an insufficient dataset for click-through rates. Furthermore, six different machine learning algorithms have been assessed for predicting ad click behavior. For the experimental study, we obtained user demographic and online activity data from Kaggle, along with a binary label indicating ad clicks. To enhance the model's performance, we employed a GAN for data augmentation and generated additional training examples. We compared the machine-learning algorithm's outcomes with and without GAN-based data augmentation to evaluate its predicted accuracy. According to the findings, most algorithms have increased sensitivity and specificity after utilizing GAN to augment the data, indicating that the generated data has improved their ability to accurately distinguish positive and negative events. GAN-based data augmentation boosted all models to varying degrees, according to the findings
Dijital İkizlerle Enerji Santrallerinin Yönetimi: Hidroelektrik, Güneş, Rüzgâr, Termik Santrallar ve Batarya Depolama Sistemleri
No full textClinical evaluation of in-office bleaching with low, medium, and high concentrate hydrogen peroxide: a 6-month a double-blinded randomized controlled trial
No full textObjective The study evaluated the longevity, efficacy, sensitivity, and impact on the oral health-related quality of life of in-office dental bleaching using low, medium, and high concentrate hydrogen peroxide. Material and Methods Randomized, parallel, and double-blinded clinical trial was performed with 54 participants using18% hydrogen peroxide (HP), 25%HP, and 40%HP in-office bleaching agent. Tooth color was evaluated at baseline, after the 1st session bleaching, after the 2nd session bleaching and 6 months after finishing the bleaching using spectrophotometer. Tooth sensitivity (TS) was measured with the Visual Analog Scale at baseline, immediately after bleaching, after 1 day, and after 7 days. The impact on quality of life was evaluated using the 14-item Oral Health Impact Profile (OHIP-14) questionnaire at baseline, and 6 months after bleaching. The data were analyzed using the Kikare test, Kruskal Wallis test, one-way ANOVA, Wilcoxon, Friedman, Mann-Whitney (p 0.05), surpassing perceived value. There was no difference in TS levels among groups at all evaluation times (p > 0.05). TS significantly increased after bleaching (p 0.05). All groups reported improved aesthetic self-perception following bleaching (p 0.05). Conclusion Low, medium, and high concentrations of HP did not affect both the final tooth color and the reported TS intensity, regardless of the evaluation time. In-office bleaching provides positive effects on aesthetic perception and different HP concentrations have not influenced this positive effect. Clinical significance In this study, the efficacy, longevity, sensitivity, and impact on oral health-related quality of life of in-office bleaching using low, medium, and high concentration hydrogen peroxide agents from the same manufacturer were found to be similar. However, these results cannot be extrapolated to other in-office high-concentration hydrogen peroxide gels
Routing and payload planning of multi-base, heterogeneous fleet unmanned aerial vehicles to time-windowed missions
No full textAskeri teknolojilerin hızla gelişmesi, konvansiyonel harp kavramının dönüşmesine ve farklılaşmasına neden olmuş, bu bağlamda hibrit savaş kavramı ortaya çıkmıştır. Bu yeni savaş konseptiyle muharebe ortamlarının etki alanları genişlemiş ve değişim geçirerek birçok alanda yönetilen bir kavram haline gelmiştir. Bu değişim, farklı savaş ekipman ve teçhizatlarının kullanımını zorunlu kılmıştır. Son yıllarda savaşlara en çok etki eden askeri teknolojilerden biri İnsansız Hava Araçları (İHA)'dır. Gelişmiş ordulara sahip devletler, bu savaş ekipmanlarını envanterlerinde bulundurarak askeri operasyonlarda yoğun şekilde kullanmaktadır. Ancak muharebe ortamındaki başarı, yalnızca bu teknolojilerin envanterde bulundurulmasına değil, bu teknolojilerin etkin bir şekilde planlanmasına da bağlıdır. Bu çalışmada, her askeri operasyonun öncesinde veya gerçekleştiği esnada yapılması gereken; istihbarat toplama ve fiziksel saldırı görevlerinin gerçekleştirileceği minimum maliyetli yol planlamasını ve irtifa seviyelerini bulmak için bir karma tam sayılı doğrusal programlama modeli önerilmiştir. Geliştirilen model irtifa seviyelerini modelin bileşeni olarak ele alması, rotalamayı yaparken göreve uygun faydalı yük planlamasını gerçekleştirmesi ve İHA’ların faydalı yük kapasitesi, asma noktası sınırı, havada kalma süresi gibi tüm fiziksel kısıtlamalarını gözeterek görev atamasını gerçekleştirmesiyle literatürdeki diğer modellerden ayrılmaktadır. Geliştirilen model küçük, orta ve büyük ölçekli 9 farklı senaryoda test edilip çözümler sunulmuştur. Ayrıca minimum mesafeli yol planlarıyla mevcut çözümler karşılaştırılarak duyarlılık analizi gerçekleştirilmiştir. Sonuçlar tartışılarak gelecek çalışmalara öneriler getirilmiştir.</p
Cross-cultural adaptation, validity, and reliability study of shortened version of the Vestibular Activities and Participation Measure into Turkish
No full textAbstractBackgroundVestibular disorders significantly impact daily activities and participation, leading to reduced quality of life. The Shortened Vestibular Activities and Participation Measure (VAP) is a 12-item tool designed to assess activity limitations and participation restrictions in individuals with vestibular disorders.ObjectiveIn this study, the Turkish Shortened VAP was translated and culturally adapted. Its validity and reliability were also assessed.MethodsA total of 123 participants with vestibular disorders were included. The translation and cultural adaptation followed standard guidelines. Structural validity was assessed through exploratory and confirmatory factor analyses, and convergent validity was evaluated using correlations with the Dizziness Handicap Inventory (DHI). Reliability was examined using internal consistency (Cronbach’s alpha and McDonald’s omega) and item analysis.ResultsFactor analyses confirmed the two-factor structure with good fit indices (GFI = 0.938). Significant correlations with the DHI supported convergent validity (r = 0.65). Internal consistency was strong for the total scale (Cronbach’s α = 0.85; McDonald’s ω = 0.91) and acceptable for subscales. All items demonstrated acceptable corrected item-total correlations.ConclusionsThe Turkish Shortened VAP is a valid and reliable tool for assessing activity limitations and participation restrictions in vestibular disorders, suitable for clinical and research use in Turkey.</section