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Hygrothermal performance of diatomite PCM composite walls for energy-efficient construction in hot-arid climates
No full textIn response to the growing demand for energy-efficient construction materials tailored to hot-arid climates, this study proposed and rigorously evaluated an innovative composite wall system that synergistically combined diatomite with paraffin. Eight wall assemblies were subjected to detailed numerical simulations, including five hollow brick walls with varied internal and external finishing layers and three concrete walls differentiated by aggregate composition. To ensure contextual relevance, the study incorporated real meteorological data from three representative desert locations: Ghardaïa (Algeria), Djerba Mellita (Tunisia), and Abu Dhabi (United Arab Emirates). In parallel, a dual-compartment experimental apparatus was developed to investigate the coupled thermal and hygric behavior of mortar and concrete composites under controlled environmental conditions. These experimental measurements provided critical physical insights and served to validate the finite element model, achieving deviations below 5% and thereby confirming the robustness of the numerical framework. The results demonstrated that the use of diatomite either alone or in combination with paraffins whether as finishing layers or as a partial replacement for sand and gravel in mortar and concrete mixtures significantly improved hygrothermal regulation. These systems effectively reduced internal heat flow and maintained temperature and humidity within comfort thresholds. Among all configurations, the brick wall with both internal and external finishes made from diatomite and 12% paraffin was identified as the most innovative and high-performing configuration, achieving up to a 40% reduction in heat flux while ensuring superior thermal insulation and humidity stability
Critical Examination of Security Evaluation Tools for Docker Images∗
No full textDocker, a widely used platform for containerization in software development, brings convenience but also introduces security concerns. Unresolved vulnerabilities within Docker images can result in substantial financial losses and compromise sensitive data. This study delves into the efficacy of vulnerability scanning tools within Docker environments, particularly focusing on Trivy, Grype, and Snyk. To assess the performance of scanning tools, 439 Docker images were analyzed. The scanning results were evaluated using the VSM and SVSM methods, which were proposed in this study alongside traditional metrics based on vulnerability counts commonly used in the literature. The proposed evaluation metrics take into account not only the number of vulnerabilities but also the severity levels of them. Our findings reveal that even the most effective scanning tool fails to detect a significant number of vulnerabilities in Docker images. Using multiple scanning tools together was found to be more effective in detecting vulnerabilities, even if the second scanning tool detected fewer
Hotel Guests’ Perceptions of Sustainable Tourism Practices Within the Framework of Cue Utilization Theory: An Analysis of a Worldwide Online Travel Platform’s Sustainability-Certified Hotels
No full textPeriodic solutions and asymptotic properties of first order linear nonhomogeneous neutral delay differential equations
No full textThis article concerns first-order linear nonhomogeneous neutral delay differential equations with periodic coefficients and constant delays, where the coefficients share a common period and the delays are multiples of this period. First, we obtain periodic solutions of linear nonhomogeneous neutral delay differential equations using the variation of parameters method. These periodic solutions are expressed analytically. Two examples demonstrating the applicability of our results are also included. Second, we investigate the asymptotic behavior and estimation of solutions to linear nonhomogeneous neutral delay differential equations. The results are obtained using an appropriate real root of the relevant characteristic equation. Three examples are given to illustrate our results. Finally, we present the special case of first-order linear nonhomogeneous neutral delay differential equations with constant coefficients and constant delays, and provide an interesting example
The effect of motor skills and imagery application on psychomotor development in children
No full textThis study aimed to investigate the psychomotor development effect of motor skills and imagery application in 13 year-old boys. The research group consisted of 40 male volunteer children who had 13 studied at Kocaeli/İzmit 29 Ekim Secondary School. The research groups were divided into four groups (control, experiment-1, experiment-2, experiment-3) had 13 with a random method as n=10 children per group. A skill track consisting of eight stations, including fine and gross motor skills, was applied as a data collection tool. Motor skills and imagery programs were applied to the experimental groups 2 days a week for 8 weeks. The control group did not participate in imagery and motor skills exercises. The station scores and track finishing time that constitute the results of the pre- and post-tests of the intervention were recorded. Data analysis was performed using SPSS 21.0. According to the normality test results, the Wilcoxon test, Kruskal–Wallis test, paired samples test, and one-way ANOVA test were applied. There were statistically significant differences between the study groups in balance, ball transport with racket, target ball throwing, cross hopping, ball driving, shooting, and over the hurdles practice post-test station score averages (p<0.05). There were significant differences between the total score on the track and the post-test averages of the track finish time (p<0.05). Imagery application studies are important mental processes in the uptake of motor learning and motor development. This research, which will be a reference for future studies, emphasizes the importance of mental preparation and states that the repetitive physical work method is also effective
Generative Artificial Intelligence as a Linguistic Crutch or Cognitive Scaffold: The Interplay of Self-Beliefs and General English Proficiency in English Medium Instruction
No full textThis study examines how self-efficacy, self-regulation, and generative artificial intelligence (GenAI) -related factors interact to shape academic success and general English proficiency (GEP) within an EMI context. It draws on data from 754 EMI students at a major public university in Turkey, focusing on the social sciences and engineering disciplines. The findings reveal that for social science students, besides GEP, a positive perception towards GenAI, self-efficacy, and self-regulation are key to academic achievement—self-belief and the ability to regulate one's learning are essential for mastering both language and content. For engineering students, however, success is primarily driven by GEP, GenAI competence, and a positive perception toward GenAI. When it comes to GEP, social science students benefit from GenAI competence to improve their language skills, while engineering students rely more on self-efficacy and self-regulation. Additionally, excessive time spent on GenAI platforms is correlated to poorer academic outcomes, highlighting the importance of quality over quantity in GenAI engagement. The findings are discussed, and implications for enhancing EMI strategies are presented
Transcatheter Tricuspid Valve-in-Valve Replacement in a Patient with Ebstein Anomaly Ebstein Anomalisi Olan Bir Hastada Transkateter Triküspit Kapak-İçinde-Kapak Değişimi
No full textHydrogen production via methanolysis of sodium borohydride using La<sub>2</sub>O<sub>3</sub> and La<sub>2</sub>O<sub>2</sub>CO<sub>3</sub> nanowire catalysts
No full textCatalyst design is of great importance for hydrogen production from solid hydrogen storage materials such as NaBH4. For this purpose, lanthanum-based La2O3 and La2O2CO3 nanowire catalysts were synthesized via a hydrothermal method, followed by calcination at different temperatures (700 degrees C and 500 degrees C, respectively) to obtain the desired crystalline phases. Their activities in NaBH4 solvolysis were then investigated. Accordingly, La2O2CO3 nanowire catalyst catalyzed NaBH4 methanolysis 3.4 times faster than the other reactions, exhibiting the highest hydrogen production rate at 0.5 min (HPR0.5m, 6939 mLH2/(gcat*min)) and equivalent H2 (4.03) values. Kinetic studies of NaBH4 methanolysis in the presence of the La2O2CO3 nanowire catalyst calculated the activation energy as 32.09 kJ/mol. Furthermore, even after 3 months of isolation, the reused La2O2CO3 nanowire catalyst retained 76.67% of its catalytic activity. All findings indicate that La2O3 and La2O2CO3 nanowire catalysts significantly increase hydrogen production efficiency, highlighting their potential for practical application in clean energy and hydrogen storage technologies
E-TİCARET LOJİSTİĞİNDE DİJİTALLEŞME: LOJİSTİK 4.0, OTONOM SİSTEMLER VE DENİZ TAŞIMACILIĞINA ETKİLERİNİN HUKUKİ DÜZENLEMELER BAĞLAMINDA İNCELENMESİ
No full textE-ticaretin ve dijital lojistik uygulamalarının hızla yaygınlaşması, uluslararası taşımacılıkta kullanılan geleneksel hukuki yapıların dijital sistemler karşısındaki yeterliliğini tartışmalı hâle getirmiştir. Özellikle dijital taşıma belgeleri, blokzincir tabanlı sözleşmeler ve otonom taşıma sistemleri, mevcut uluslararası taşıma hukuku rejimlerinin bu yeni uygulamalara ne ölçüde uyum sağlayabildiği sorusunu gündeme getirmektedir. Bu çalışma, Lojistik 4.0 bağlamında ortaya çıkan söz konusu dijital uygulamaların, mevcut uluslararası taşıma kurallarıyla ne ölçüde örtüştüğünü incelemeyi amaçlamaktadır. Araştırma, nitel bir normatif-doktrinel ve karşılaştırmalı hukuk analizi olarak kurgulanmış; CMR Konvansiyonu, Lahey-Visby, Hamburg ve Rotterdam Kuralları’nda taşıma belgeleri ve konişmentolara ilişkin hükümler madde bazında analiz edilmiştir. Karşılaştırmalı değerlendirme, belgenin hukuki niteliği, elektronik belgeye tanınan statü, belge tekilliği ve kontrol mekanizmaları ile devredilebilirlik ölçütleri temelinde gerçekleştirilmiştir. Analiz sonucunda, CMR, Lahey-Visby ve Hamburg Kuralları’nın dijital taşıma belgeleri ve otonom sistemler bakımından sınırlı veya örtük çözümler sunduğu; buna karşılık Rotterdam Kuralları’nın elektronik taşıma belgelerini açıkça tanıyan ve dijital lojistik uygulamalarıyla daha uyumlu bir normatif çerçeve sunduğu tespit edilmiştir. Çalışma, özellikle e-CMR Ek Protokolü ve Rotterdam Kuralları çerçevesinde, uluslararası taşıma hukukunun dijital dönüşüm karşısında güncellenmesi gerektiğini ortaya koymaktadır.The rapid proliferation of e-commerce and digital logistics applications has called into question the adequacy of traditional legal frameworks used in international transportation when faced with digital systems. In particular, digital transport documents, blockchain-based contracts, and autonomous transport systems raise the question of the extent to which existing international transport law regimes can adapt to these new applications. This study aims to examine the extent to which these digital applications, emerging in the context of Logistics 4.0, align with existing international transport rules. The research is structured as a qualitative normative-doctrinal and comparative legal analysis; provisions regarding transport documents and bills of lading in the CMR Convention, the Hague-Visby, Hamburg, and Rotterdam Rules have been analyzed on a clause-by-clause basis. The comparative assessment was conducted based on the legal nature of the document, the status granted to electronic documents, document uniqueness and control mechanisms, and transferability criteria. The analysis concluded that the CMR, Hague-Visby, and Hamburg Rules offer limited or implicit solutions regarding digital transport documents and autonomous systems; in contrast, the Rotterdam Rules explicitly recognize electronic transport documents and provide a normative framework more compatible with digital logistics applications. The study highlights the need to update international transport law in light of digital transformation, particularly within the framework of the e-CMR Additional Protocol and the Rotterdam Rules.</p