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V570 Per: Characterization of a Benchmark Eclipsing Binary
No full textThis study presents a comprehensive analysis of the detached binary system V570 Per through combined
photometric, spectroscopic, and astrometric observations. By disentangling the composite spectra, precise
fundamental parameters and detailed chemical abundances were determined for both stars. The primary
component has a mass of 1.4569 0.0100
+0.0094 M⊙, a radius of 1.543 0.009
+0.012 R⊙, an effective temperature of 6556 26
+64 K, and
a metallicity of 0.18 0.01
+ +0.03 dex, while the secondary has a mass of 1.3579 0.0089
+0.0094 M⊙, a radius of 1.377 0.015
+0.013 R⊙,
an effective temperature of 6468 21
+32 K, and a metallicity of 0.15 0.01
+ +0.02 dex. The system is estimated to be
577 60
+60 Myr old with a synchronized orbit. The available O − C data imply a minimum mass of 0.57M⊙
or 0.11M⊙ for the third body, corresponding to eccentric and circular orbits, respectively. MESA evolutionary
models indicate that the primary will fill its Roche lobe and begin mass transfer to the secondary in about 2.8 Gyr,
whereas the secondary will reach the terminal-age main sequence in approximately 3.2 Gyr. The chemical
composition of both stars shows remarkable consistency, confirming their common origin, except for calcium,
which is significantly enhanced in the primary. Line measurements support this difference and are therefore
interpreted as an intrinsic abundance variation rather than an artifact of the analysis. The overall solar-rich
metallicity, combined with a relatively low α-element content, links V570 Per to the Galactic thin-disk
population. In addition, Galactic orbit analyses of open clusters in the solar neighborhood have revealed that the
V570 Per system may have originated from the Melotte 25 open cluster
Architectural and Social Examination of the Ottoman Social Complex System on the Foundation Certificate of Nişancı Mehmed Pasha
No full textBu çalışma, Osmanlı Klasik Dönem külliye mimarisinin geç örneklerinden biri olan Nişancı Mehmed Paşa Külliyesi’nin vakfiyesi üzerinden, mimarlık tarihi ve şehir tarihi bağlamında kapsamlı bir değerlendirme sunmaktadır. Bazı araştırmacılar tarafından Mimar Sinan’ın son eseri kabul edilen bu külliyenin birçok yapısı günümüze ulaşamamıştır. Bu sebeple, külliyenin mimari organizasyonu, sosyal ve vakıf sistemiyle bağlantılı işleyişi hakkında en önemli kaynak vakfiye metnidir.
Bu çalışmada daha önce arşiv uzmanları tarafından transkripsiyonu yapılmış fakat yayımlanmamış vakfiyenin mimarlık tarihi açısından sistematik biçimde analiz edilerek içerdiği tarihî verilere eklenen değerlendirme ile vakfiyede yer alan bilgilerin birçok saha için yönlendirici nitelikte olması hedeflenmektedir. Çalışma kapsamında, vakfiyenin satır aralarından Mimar Sinan’ın Osmanlı sanatının zirvesinde tasarladığı son yapının inşa gerekçesi, mekânsal organizasyonu, görevlendirmeleri, toplumsal beklentileri ve dönemin mimari üslubuna dair çıkarımlar yapılmıştır. Böylece Mimar Sinan sonrası külliye kavrayışının devamlılığı ve dönemin devlet ricalinin mimariye müdahale biçimleri üzerine yeni bir katkı sunmak amaçlanmaktadır.This study examines the Nişancı Mehmed Pasha Social Complex, one of the later examples of classical Ottoman complex architecture, through an architectural history-based analysis based on the foundation certificate text. A significant portion of the structures belonging to the social complex, considered by some researchers to be Mimar Sinan's last work, have not survived to the present day. This situation makes the foundation certificate a fundamental source for understanding the social complex's architectural design, its functional components, and the social and institutional structure that took shape as a result.
In this study, the foundation certificate, which had previously been transcribed by archive specialists but not published, is evaluated from an architectural history perspective; the historical content of the text is approached with an interpretative approach. The aim of the research is to reveal the multi-layered information provided by the data in the foundation certificate text about the establishment of the architectural space, building types, staff, social expectations, and the architectural understanding of the period. Through readings between the lines of the foundation certificate, the reasons for the construction of this social complex, built during the mature period of Ottoman art and considered to be Mimar Sinan's last design, and its spatial and functional organization have been examined together. In this context, this study aims to contribute to the assessments of post-Sinan building social complex design and to understanding the role of Ottoman state officials in architectural production processes
Development of a Self-Efficacy Scale for Arabic Reading Comprehension Among High School Students
No full textThis study aimed to develop a self-efficacy scale to assess high school students’ perceived competence in Arabic reading comprehension. Accordingly, a draft version of the ‘‘High School Students’ Self-Efficacy Scale for Arabic Reading Comprehension’’ was constructed as a 5-point Likert-type instrument. Following expert evaluations (n = 8), the initial pool of 46 items was reduced to a 23-item trial form based on content validity analysis. Exploratory factor analysis (EFA) was conducted with data from 210 students, while confirmatory factor analysis (CFA) was performed with a separate sample of 473 students. In this study, EFA and CFA were performed on separate samples. While this is methodologically appropriate, it may have constrained the model’s fit. Moreover, the use of an all-male sample for the EFA presents a potential limitation in terms of demographic diversity. EFA results indicated a unidimensional structure. The CFA results demonstrated acceptable model fit indices (RMSEA = 0.06, x2/df = 2.59, GFI = 0.87, CFI = 0.95), confirming the construct validity of the scale. The internal consistency of the scale was found to be high, with a Cronbach’s alpha coefficient of .957. Although the scale demonstrated strong psychometric properties, the absence of gender diversity in the EFA sample and the lack of subsequent invariance testing are acknowledged as limitations. Nevertheless, despite these constraints, the developed scale represents a valuable tool for educators, researchers, and curriculum developers aiming to assess high school students’ self-efficacy in Arabic reading comprehension
An Adaptive Hybrid Metaheuristic Algorithm for Lung Cancer in Pathological Image Segmentation
No full textBackground/Objectives: Histopathological images are fundamental for the morphological diagnosis and subtyping of lung cancer. However, their high resolution, color diversity, and structural complexity make automated segmentation highly challenging. This study aims to address these challenges by developing a novel hybrid metaheuristic approach for multilevel image thresholding to enhance segmentation accuracy and computational efficiency. Methods: An adaptive hybrid metaheuristic algorithm, termed SCSOWOA, is proposed by integrating the Sand Cat Swarm Optimization (SCSO) algorithm with the Whale Optimization Algorithm (WOA). The algorithm combines the exploration capacity of SCSO with the exploitation strength of WOA in a sequential and adaptive manner. The model was evaluated on histopathological images of lung cancer from the LC25000 dataset with threshold levels ranging from 2 to 12, using PSNR, SSIM, and FSIM as performance metrics. Results: The proposed algorithm achieved stable and high-quality segmentation results, with average values of 27.9453 dB in PSNR, 0.8048 in SSIM, and 0.8361 in FSIM. At the threshold level of T = 12, SCSOWOA obtained the highest performance, with SSIM and FSIM scores of 0.9340 and 0.9542, respectively. Furthermore, it demonstrated the lowest average execution time of 1.3221 s, offering up to a 40% improvement in computational efficiency compared with other metaheuristic methods. Conclusions: The SCSOWOA algorithm effectively balances exploration and exploitation processes, providing high-accuracy, low-variance, and computationally efficient segmentation. These findings highlight its potential as a robust and practical solution for AI-assisted histopathological image analysis and lung cancer diagnosis systems
A Microstrip Monopole Antenna Design for 5G Sub-6 GHz Applications Using Deep Learning
No full textThis study presents the design and optimization of a microstrip monopole antenna for 5G sub-6 GHz applications, employing a deep learning-based surrogate model combined with honeybee mating optimization (HBMO). The studied antenna structure employs air via arrays, intended to enhance antenna performance, including improved impedance matching and increased bandwidth. It is important to note that, unlike conventional antennas, the proposed design does not include a fully enclosed metallic cavity similar to a substrate integrated waveguide (SIW) antenna designs. A sensitivity analysis was conducted to assess the impact of these parameters, emphasizing the need for optimal tuning. To generate training and test datasets efficiently, Latin hypercube sampling (LHS) was used. A convolutional neural network (CNN) surrogate model was trained, outperforming other machine learning (ML) algorithms in predictive accuracy and generalization. The proposed CNN-HBMO framework reduced computational costs by minimizing the need for expensive electromagnetic (EM) simulations, enabling rapid design space exploration. The optimized antenna was fabricated and validated through experimental measurements, achieving 2–3 dBi gain and 11 < − 10 dB across the 2.7–5.2 GHz band. Compared to existing designs, the proposed antenna offers a compact size (34 ×34 mm) with competitive performance, making it suitable for multi-band 5G applications
Bioactive 3D Bioprinted N,S-Graphene Quantum Dot Reinforced Nanocellulose/Fucoidan Scaffolds for Wound Healing
No full textThe development of printable bioinks that simultaneously possess superior rheological fidelity and multifunctional
bioactivity remains a critical challenge in extrusion-based 3D bioprinting for tissue engineering.
Herein, we engineered a novel nanocomposite hydrogel scaffold comprising a structural Cellulose Nanofiber
(CNF) backbone and a bioactive Fucoidan (FUC) matrix, reinforced with hydrothermally synthesized Nitrogen
and Sulfur co-doped Graphene Quantum Dots (N,S-GQDs). Comprehensive physicochemical characterization
confirmed the successful integration of ultrasmall (~9.28 nm), crystalline N,S-GQDs into the polymer network.
Rheological analysis revealed that the incorporation of GQDs significantly modulated the viscoelastic properties;
all formulations exhibited characteristic non-Newtonian pseudoplastic (shear-thinning) behavior beneficial for
extrusion, while the storage modulus (G') consistently dominated the loss modulus (G") across the frequency
range, indicating the formation of a stable, solid-like gel structure with enhanced shape fidelity post-printing.
Beyond mechanical reinforcement, the nanocomposites demonstrated exceptional biological functionality. The
optimized scaffolds exhibited potent, dose-dependent antibacterial activity against Staphylococcus aureus,
Escherichia coli, and Pseudomonas aeruginosa, alongside a significant anti-inflammatory efficacy characterized by
a 78.4% inhibition of protein denaturation. In vitro biological assessments revealed a transition from passive
biocompatibility to active regeneration; the scaffolds induced a remarkable proliferative response in L929 fibroblasts,
with cell viability exceeding 140% over 14 days. Furthermore, in a proliferation-independent scratch
assay, the GQD-functionalized hydrogels significantly accelerated fibroblast migration, achieving near-complete
wound closure (99.8%) within 48 h compared to 55.3% in the control group. These findings collectively establish
the 3D printed CNF/FUC/N,S-GQD hydrogels as a robust, rheologically tunable, and bioactive “all-in-one”
platform for advanced wound healing strategies
TripletMAML: A Metric-Basedmodel-Agnostic Meta-Learning Algorithm for Few-Shot Classification
No full textIn this paper, we introduce TripletMAML, a new meta-learning algorithm that enhances the Model-Agnostic Meta-Learning
(MAML) approach by incorporating a metric-learning dimension. This enhancement involves the adoption of MAML’s
optimization strategies while transitioning to a triplet network model to facilitate metric learning. A novel aspect of this
approach is our triplet-task generation technique, designed to produce meta-learning tasks with triplets for both 1-shot and
5-shot settings. TripletMAML extends MAML by jointly incorporating metric-learning and optimization-based principles
through a triplet-task formulation, offering a unified and effective framework for few-shot classification.We evaluate Triplet-
MAML’s effectiveness across four well-known few-shot image classification benchmarks, comparing its performance against
a range of baseline methods. Our findings indicate that TripletMAML, even without data augmentation or extensive hyperparameter
adjustments, significantly improves MAML’s performance and surpasses competing baseline approaches in both
1-shot and 5-shot settings. We also demonstrate that optimizing the hyper-parameters automatically using differential evolution
method can elevate TripletMAML’s performance to that of more sophisticated models. Additionally, we conduct image
retrieval experiments to ascertain whether TripletMAML’s few-shot classification training provides a good starting point for
addressing few-shot image retrieval challenges
Hot-Pressing Process of 7075 Aluminum Alloy: Microstructure, Corrosion and Wear Properties
No full textIn this study, 7075 aluminum alloy was fabricated by hot-pressing process with various production temperatures and times. It was also aimed to reveal the effects of hot-pressing process parameters on microstructure, corrosion and wear properties of the 7075 aluminum. Samples were produced at 450 C, 475 C and 500 C with 30-min and 60-min process duration under 200 MPa pressure and 0.1-bar vacuum. Microstructural analysis revealed that the magnesium- and zinc-containing secondary phases decomposed under the enhanced steady cooling conditions, which facilitated sufficient diffusion. It was observed that continuous grain boundary phases transformed into a discontinuous structure via the diffusion of magnesium with increasing process temperature. The corrosion behavior of the samples was dependent on the microstructure, and also the discontinuous morphology of the magnesium- and copperrich secondary phases decreased the corrosion rate down to 0.1746 mm/year. On the other hand, the formation of secondary phases negatively affected the wear resistance, and lower surface damage was obtained in samples produced at 450 C for 30 minutes and 60 minutes
The Effect of Physical Comfort on User Productivity in Open-Plan Office Spaces
Full text linkAçık plan ofisler 21.yy’da giderek daha popüler hale gelmekte, fiziksel ortamlarının verimlilik üzerindeki
etkileri de tartışma konusu olmaktadır. Açık plan ofislerde fiziksel ortam, kullanıcı verimliliğini önemli
ölçüde etkileyebilir. Ofis ortamında hedeflenen konforun sağlanamaması; kullanıcılarda hastalık veya
memnuniyetsizlik gibi sorunlara neden olabilmektedir. Çalışmanın amacı, açık plan ofislerde fiziksel
ortamın verimliliğe etkilerini inceleyerek, daha konforlu ofis mekanları oluşturulması için literatüre katkı
sağlamaktır. Çalışma, Kayseri’de hizmet veren belediye yapıları örnekleminde, kullanıcılardan anket
yapılarak edinilen nitel verilerin, SPSS programında analiz edilmesi ve nicel sonuçlara varılması şeklinde
oluşturulmuştur. Analiz sonuçları doğrultusunda, fiziksel çalışma ortamı ve verim arasındaki ilişki, fiziksel
çalışma ortamı ve sağlık arasındaki ilişki, fiziksel çalışma ortamının çalışan verimi ve cinsiyet ilişkisi,
fiziksel çalışma ortamının çalışan sağlık durumu ve cinsiyet ilişkisi durumları sorgulanmaktadır. Açık plan
ofislerdeki fiziksel konfor faktörleri ile kullanıcı sağlığı ve kullanıcı verimliliği arasındaki ilişkiler, Pearson
Korelasyon Testi ile incelenmiş, kuvvetli ve kuvvetliye yakın ilişki düzeyleri belirlenmiştir. Açık plan
ofislerdeki fiziksel çalışma ortamlarının, kullanıcı verimliliğine etkisi ile cinsiyet ilişkisi ve açık plan
ofislerdeki fiziksel çalışma ortamları ile kullanıcı sağlık durumu ve cinsiyet ilişkisi, independent sample ttest
ile incelenmiş, aralarında anlamlı ilişki olduğu görülmüştür. Fiziksel ortam konfor düzeylerinin çalışan
verimliliği üzerinde önemli bir etkiye sahip olabileceği sonucuna varılmıştır.Open-plan offices are becoming increasingly popular in the 21st century, and the impact of their physical
environment on productivity is a subject of debate. The physical environment in open plan offices can
significantly affect user productivity. Failure to provide the targeted comfort in the office environment may
cause problems such as illness or dissatisfaction in users. The aim of the study is to contribute to the literature
by examining the effects of physical environment on productivity in open plan offices and to create more
comfortable office spaces. The study was formed by analyzing the qualitative data obtained from the users
through a questionnaire in the sample of municipal buildings serving in Kayseri by using the SPSS program
and reaching quantitative conclusions. In line with the results of the analysis, the relationship between
physical working environment and productivity, the relationship between physical working environment and
health, the relationship between physical working environment and employee productivity and gender, the
relationship between physical working environment and employee health status and gender are questioned.
The relationships between physical comfort factors in open plan offices and user health and user productivity
were examined with Pearson Correlation Test, and strong and close to strong relationship levels were
determined. The relationship between the effect of physical working environments in open plan offices on
user productivity and gender, and the relationship between physical working environments in open plan
offices and user health status and gender were examined with independent sample t-test, and a significant
relationship was found between them. It was concluded that physical environment comfort levels may have
a significant impact on employee productivity
Unveiling the Origins and Dynamics of the Hierarchical Triple Star System CN Lyn
Full text linkIn this study, we present a detailed analysis of CN Lyn, an overlooked triple star system, by combining spectroscopic data from the literature, photometric Transiting Exoplanet Survey Satellite data, and kinematic techniques. We updated the fundamental parameters of the known eclipsing components in the system with high precision. The chemical composition of both eclipsing components (Aab) and the third component (B) in the system were calculated with great accuracy. According to our analysis the mass, radius, and metallicity of the eclipsing components are 1.166-0.012+0.013M circle dot , 1.786-0.014+0.013R circle dot , and -0.78-0.02+0.02 dex for Aa and 1.143-0.012+0.013M circle dot , 1.651-0.013+0.014R circle dot , and -0.55-0.02+0.03 dex for Ab. The pair's age is 3.89-0.10+0.10 Gyr. The mass, radius, metallicity, and age for B are 0.85-0.23+0.23M circle dot , 1.436-0.023+0.026R circle dot , -1.83-0.11+0.09 dex, and 12.5-2.5+2.5 Gyr, respectively. It is also found that the triple system (AabB) satisfies the stability criteria for the hierarchical triple system. Kinematic and Galactic orbital parameters of CN Lyn were obtained from the astrometric and spectroscopic data of the system. Dynamical orbital analyses, taking into account the ages of the component stars in the central binary system (A), show that the CN Lyn originated at the metal-poor edge of the Galactic disk. The third component of the system was found to be a member of the halo population in terms of age, alpha elements, and metal abundance. Given the different chemical abundances and age of B compared to A, this suggests that the third component was captured by the central system in a region with weak gravitational interactions far beyond the Galactic disk