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3B Baskı ile Üretilen ABS, PLA Menteşelerin, Geleneksel Metal Menteşeler ile Karşılaştırılması
No full textFurniture designed to serve activities such as storage, working, dining, sitting, and lying down in indoor and outdoor spaces includes various fixing and connecting elements to ensure the necessary durability and functionality. Among these are screws, minifix fittings, rails, and hinges. In this study, the strength of leaf hinges made from metal using traditional methods and those produced with PLA and ABS filaments using a 3D printer was compared in storage furniture with doors. The study involved leaf hinges produced from three different materials and two types of wood-based materials (MDF and particle board). The designed hinges were mounted on cabinet doors made of MDF and particle board and tested in accordance with the TS 9215 standard. Three different loads (30 kg, 37.5 kg, and 45 kg) were applied during the tests, and hinge deformations were measured. The collected data were analysed using SPSS software, revealing statistically significant differences in deformation depending on the material type. The results indicated that ABS hinges could be a viable alternative to metal hinges in terms of strength, while PLA hinges may be insufficient in certain conditions. This study provides valuable insights into the integration of cost-effective and environmentally friendly manufacturing methods into the furniture industry.İç ve dış mekanlarda depolama, çalışma, yemek yeme, oturma, uzanma gibi eylemlere hizmet etmek üzere tasarlanan mobilyalarda gerekli dayanıklılığı ve işlevselliği sağlamak üzere kullanılan bağlantı elemanları bulunmaktadır. Bu bağlantı elemanlarının arasında vidalar, minifixler, raylar ve menteşeler bulunmaktadır. Çalışma kapsamında kapaklı depolama mobilyalarında kullanılan geleneksel yöntemlerle metal malzeme ile üretilmiş yaprak menteşeler ile 3B yazıcı kullanılarak PLA ve ABS filamentler ile üretilmiş menteşelerin mukavemetleri karşılaştırılmıştır. Çalışmada 3 farklı malzemeden üretilmiş yaprak menteşeler, 2 farklı ahşap malzeme (MDF ve Yonga Levha) kullanılmıştır. Tasarlanan menteşeler, MDF ve yonga levhadan yapılmış dolap kapaklarına monte edilerek TS 9215 standardına uygun şekilde test edilmiştir. Deneylerde üç farklı ağırlık (30 kg, 37,5 kg, 45 kg) uygulanmış ve menteşelerin deformasyonları ölçülmüştür. Elde edilen veriler SPSS yazılımı ile analiz edilmiş ve malzeme türüne bağlı olarak deformasyon miktarlarında istatistiksel olarak anlamlı farklar gözlemlenmiştir. Sonuçlara göre, ABS malzeme menteşelerin dayanım açısından metal menteşelere alternatif olabileceği, PLA malzemenin ise bazı durumlarda yetersiz kalabileceği belirlenmiştir. Bu çalışma, düşük maliyetli ve çevre dostu üretim yöntemlerinin mobilya endüstrisine entegrasyonu açısından önemli bir katkı sunmaktadır
Lubrication studies of ?-lactoglobulin-stabilized emulsions mixed with bovine submaxillary mucin
No full textUnderstanding the oral processing of beta-lactoglobulin (BLG)-stabilized emulsions is crucial for optimizing the physical and sensory attributes of colloidal food systems. This study investigates the tribological properties of BLG-stabilized emulsions and their mixtures with bovine submaxillary mucin (BSM) under various contact surfaces and testing conditions. Emphasis was placed on harmonizing tribological surfaces, including hydrophilic, hydrophobic, and roughened materials, to establish mechanistically supported generalized relationships under aligned testing conditions. Wettability measurements showed superior lubrication on hydrophilic steel surfaces, whereas hydrophobic materials (HDPE, PDMS, and rough PDMS) exhibited lower wettability and higher friction. Droplet size measurements using laser diffraction and optical microscopy revealed increased flocculation and the formation of larger droplet populations (similar to 90 mu m) upon BSM addition, indicating reduced emulsion stability. Pin-on-disk tribometry indicated increased coefficients of friction (COFs) in BSM-containing emulsions at low- and mid-speed regimes, likely due to hindered droplet entrainment and inter-droplet aggregation. At high speeds, COF differences diminished due to effective fluid entrainment. Investigations with various tribopairs revealed that hydrophobic and rough surfaces hindered fluid film formation, while hydrophilic-hydrophobic interfaces, such as steel-PDMS, enhanced lubrication even with mucin present. Mini-traction machine (MTM) tests demonstrated that BSM-containing emulsions maintained lubricity at high speeds under rolling/sliding conditions. However, insufficient viscosity and low contact pressure delayed the transition to elastohydrodynamic lubrication (EHL). These findings highlight the complex interplay between emulsion droplet size, surface characteristics, and mucin's amphiphilic and flocculation-promoting behavior in boundary lubrication. The study provides mechanistic insights into food tribology, aiding the design of emulsion-based food systems with improved mouthfeel and texture.Independent Research Fund Denmark (DFF) [3164-00092B]; Republic of Turkiye Ministry of National EducationThe authors thank the Independent Research Fund Denmark (DFF, Project 3164-00092B) for financial support and the Republic of Turkiye Ministry of National Education for the PhD scholarship
Performance analysis of a parallel-counterflow vortex tube using machine learning methods
No full textIn this study, these machine learning methods (MLMs) were used for the first time in the literature to compare the temperature performance of two counterflow Ranque-Hilsch vortex tubes (RHVT) connected in parallel. As input parameters, two different pressurized fluids, three distinct materials, and six types of nozzles were selected, while the temperature difference was obtained from the hot and cold fluid outlets was designated as the output parameter. For the first time under these experimental conditions, a sensitivity analysis was conducted to determine the impact of the input parameters on the output. For each pressurized fluid and material, six models were developed using MLMs such as elastic net (EN), Bayesian ridge (BR), category boosting (CB), and light gradient boosting machine (LightGBM). A total of 30 different experimental setups were established by creating five separate setups for each model. The performance of these models was evaluated and compared using the K-fold cross-validation method. Upon analyzing the results, the BR method demonstrated the best performance for Model 1 (air, aluminum), Model 3 (air, polyamide), Model 4 (oxygen, aluminum), Model 5 (oxygen, brass), and Model 6 (oxygen, polyamide), with R2 values of 94%, 68%, 96%, 94%, and 95%, respectively. For Model 2 (air, brass), the highest performance was achieved using the CB method, with an R2 value of 93%. In this study, the optimal cooling performance results from the two parallel-connected counterflow RHVT tubes were achieved with Model 5. This model, operating at a pressure of 700 kPa and utilizing a brass material with six nozzles, produced a cooling performance of -242.55 K. The primary contribution of this research lies in the first-time application of the specified ML methods collectively for predicting the performance of the PCRHVT system, resulting in highly accurate prediction outcomes.Scientific and Technological Research Council of Turkiye (TUBITAK)Open access funding provided by the Scientific and Technological Research Council of Turkiye (TUBITAK). The authors have not disclosed any funding
Determining the relationship between fertility health knowledge and healthy lifestyle behaviors among adult women and men
No full textAimThis study aims to determine the relationship between fertility health knowledge and healthy lifestyle behaviors in adult women and men.MethodsIt is a cross-sectional, relationship-seeking type. The research was completed with 1417 participants (921 female, 496 male) of active reproductive age living in Turkey. Data were collected online using the snowball sampling method between August 2023 and January 2024.ResultsThe women who participated in the study answered 75.620% of the Fertility Health Knowledge Survey (FHKS) correctly, and their Healthy Lifestyle Behaviors Scale (HLBS)-II mean score was 123.865 +/- 21.552. The men answered 68.770% of the FHKS correctly, and their HLBS-II mean score was 123.746 +/- 21.077. A significant relationship was found between the participants' FHKS and HLBS-II scores. Healthy lifestyle behaviors explained 14% of the total variance in fertility health knowledge in women and 4.3% in men.ConclusionsParticipants exhibited fertility health knowledge and healthy lifestyle behaviors above the mean. It was determined that healthy lifestyle behaviors are a significant determinant of fertility health knowledge
The Impact of Visual and Physical Programming-Based Science Activities on Middle School Students' 21st Century and Computational Thinking Skills
No full textYapay zekâ çağında günümüz eğitiminin temel hedeflerinden biri 21. yy becerilerine sahip yaratıcı düşünebilen, problem çözebilen, eleştirel düşünebilen, işbirliği ve iletişim becerileri kuvvetli, yenilikçi ve üretken bireyler yetiştirmektir. Bu çalışmada fen bilgisi eğiticilerinin hazırladıkları Bilgi Temelli Hayat Problemleri içeren FeTeMM'e dayalı ders planları ile görsel ve fiziksel programlama etkinliklerinin ortaokul öğrencilerinin 21.yy ve bilgi işlemsel düşünme (BİD) becerilerine etkisinin incelenmesi amaçlanmaktadır. Çalışma grubunu yaz kursuna katılan 15 ortaokul öğrencisi ve 3 fen bilgisi eğiticisi oluşturmaktadır. Uygulama iki haftada 30 saatlik müdahaleyle gerçekleştirilmiştir. Uygulamada ortaokul fen bilgisi dersi konularından güneş sistemi ve ötesi, kuvvet ve hareket, kuvvet ve enerji, yenilenebilir enerji, elektrik devreleri ile ses ve özellikleri konularında etkinlikler gerçekleştirilmiştir. Veri toplama aracı olarak Bilgi İşlemsel Düşünme Becerisi Öz-yeterlik Algısı ölçeği ile Ortaokul Öğrencilerine Yönelik 21. Yüzyıl Becerileri Ölçeği kullanılmıştır. Uygulama sonrasında eğiticilerden yarı yapılandırılmış görüşme ve yansıtıcı günlükler yoluyla ortaokul öğrencilerinin 21. yy ve BİD becerilerine ilişkin görüşleri alınmıştır. Nicel veriler Wilcoxon İşaretli Sıralar testiyle analiz edilmiş, nitel veriler ise içerik analizi yöntemiyle incelenmiştir. Bulgulara göre etkinliklerin ortaokul öğrencilerinin 21.yy düşünme becerileri ve bilgi işlemsel düşünme (BİD) öz yeterlik algısı üzerinde anlamlı bir fark oluşturduğu görülmüştür. Öğrencilerin 21. yy becerilerinde yüksek etki düzeyinde bir değişim olduğu, BİD öz yeterlik algılarında ise algoritma tasarlama, problem çözme, veri işleme, temel programlama ve özgüven boyutlarının hepsinde yüksek etki düzeyinde gelişme olduğu göze çarpmaktadır. Eğiticiler de nicel bulguları destekleyen şekilde öğrencilerinin 21. yy becerileri ve BİD becerilerinin uygulama sonrası geliştirdiğini düşünmektedirler. Araştırmadan elde edilen bulgular doğrultusunda uygulama sürecine ve gelecek araştırmalara yönelik öneriler sunulmuştur.In the age of artificial intelligence, one of the main goals of education today is to produce innovative and productive individuals with 21st century skills, who can think creatively, solve problems, think critically, and have strong collaboration and communication skills. This study examines the impact of STEM-based lesson plans that incorporate knowledge-based life problems (APoKS) and visual-physical programming activities on middle school students' 21st century and computational thinking (CT) skills. The study involved 15 middle school students enrolled in a summer course and three science teachers. A 30-hour intervention was delivered over two weeks, covering topics such as the solar system, force and motion, renewable energy, electrical circuits and sound. Data were collected using the Computational Thinking Skills Self-Efficacy Perception Scale and the 21st Century Skills Scale. After implementation, educators provided insight through semi-structured interviews and reflective diaries. Quantitative data were analysed using the Wilcoxon Signed Rank Test, while qualitative data were examined using content analysis. Results indicate that the activities significantly improved students' 21st century thinking and CT self-efficacy. High impact improvements were observed in algorithm design, problem solving, data processing, programming and confidence. Educators confirmed these findings, noting the development of students' 21st-century and CT skills. Recommendations for future implementation and research are provided based on the findings
Photoorganocatalytic synthesis, characterization, crystal structure of two schiff bases and their In Vitro and In Silico evaluations as cholinesterase inhibitors
No full textGiven that substances containing an imine or azomethine fragment are included in the group of physiologically active substances, the synthesis of new Schiff bases or the development of new synthesis methods for existing ones is of interest. Two Schiff bases were synthesized by the photoorganocatalytic method and characterized by elemental analysis, UV-Vis, IR spectroscopy and X-ray single-crystal analysis. The reactions were carried out under light irradiation (household lamps 2 x 15 W) with stirring at room temperature without heating, resulting in yields of 83 and 80 %, respectively for I and II. To obtain the target product, aromatic aldehydes 5-bromosalicylic aldehyde and ortho-vanillin, as well as 2-amino-5-methylpyridine, derivatives of pyridine, representatives of heterocyclic amines, were used. Compounds were prepared by the aldol condensation. Cognitive impairment, known as dementia is typically associated with disorders of the central nervous system, particularly Alzheimer's disease. The few drugs that are currently on the market are not enough to help patients with this illness live a better life. As a result, new compounds (I and II) were synthesized and produced as inhibitors of human butyrylcholinesterase (hBChE) and human acetylcholinesterase (hAChE). The compounds I and II showed dual inhibitory efficiency against hAChE with IC50 values of 25.47 and 18.90 mu M, respectively. On the other hand, the compounds showed dual inhibitory efficiency against hBChE with IC50 values of 33.68 and 30.51 mu M, respectively, according to the in vitro evaluation. Their KI constants were even lower than those of tacrine, a common medication (Kis of 38.92 +/- 5.66 mu M for hAChE and 68.52 +/- 8.40 nM for hBChE). Additionally, molecular docking and molecular dynamic studied for both enzymes and both complexes. The compounds targeting hAChE and hBChE may offer potential benefits in the treatment of neurodegenerative diseases. By influencing cholinergic signaling, these compounds could aid in symptom management. The comprehensive analysis of the 100 ns MD simulations for both I and II with hAChE and hBChE underscores the critical role of ligand-protein interactions in drug development
Electric automobile perception of generation Z: A future perspective for sustainable development
No full textAmaç – Elektrikli otomobiller, fosil yakıtlara olan bağımlılığı azaltarak sürdürülebilir kalkınma hedeflerine ulaşmada önemli bir rol oynar. Ancak, Türkiye’de elektrikli araçların pazar payı hala düşüktür ve tüketicilerin bu araçları benimsemesini engelleyen çeşitli faktörler bulunmaktadır. Bu noktada geleceğin otomobil kullanıcılarına ilişkin bir projeksiyon oluşturmaya olan ihtiyaç artmaktadır. Çalışmanın amacı, Z kuşağının elektrikli otomobillere dair tutum ve algılarını belirleyerek, sürdürülebilirlik anlayışının elektrikli otomobillerin benimsemesindeki rolünü ortaya çıkarmaktır. Yöntem – Nitel araştırma yaklaşımına dayalı gerçekleştirilen bu çalışmanın örneklemini Ankara’nın metropol ilçelerinde yaşayan Z Kuşağı bireyleri oluşturmaktadır. Araştırma verileri yarı yapılandırılmış görüşme yöntemi ile toplanmıştır. Elde edilen veriler MAXQDA 2020 yazılımı ile tematik olarak analiz edilmiştir. Bulgular – Elektrikli araçların çevre dostu olması, Z kuşağının bu araçları benimsemesini olumlu yönde etkileyen ana faktörlerden biridir. Ancak, fiyat engelleri ve şarj altyapısındaki yetersizlikler, benimseme sürecini kısıtlayan önemli engeller olarak ortaya çıkmaktadır. Tartışma- Bulgular, elektrikli otomobillerin benimsenmesi konusunda Z kuşağının karşılaştığı motivasyon ve engellerin, politika yapıcılar ve sektör temsilcileri tarafından dikkate alınması gereken önemli faktörler olduğunu göstermektedir. Çalışma sonuçları doğrultusunda elektrikli araçların geleceğine dair çeşitli öneriler sunulmuştur. Araştırma, sınırlı coğrafi kapsamı ve katılımcı çeşitliliği nedeniyle genelleştirilebilirdik açısından sınırlamalara sahiptir. Bu çalışma, gelecekteki politika yapıcılar ve sektör temsilcileri için stratejik kararlar alırken dikkate alınması gereken önemli içgörüler sunmaktadır.Purpose – Electric automobiles play an important role in achieving sustainable development goals by reducing dependence on fossil fuels. However, the market share of electric vehicles in Türkiye is still low, and various factors prevent consumers from adopting these vehicles. At this point, the need to create a projection of future automobile users increases. The aim of the study is to determine the attitudes and perceptions of Generation Z towards electric vehicles and to reveal the role of sustainability in the adoption of electric vehicles. Design/methodology/approach – The sample of this study, which is based on a qualitative research approach, consists of Generation Z individuals living in the metropolitan districts of Ankara. The research data were collected through semi-structured interviews. The data obtained were analyzed thematically with MAXQDA 2020 Results – The environmental friendliness of electric vehicles is one of the main factors that positively affect Generation Z's adoption of these vehicles. However, price barriers and inadequacies in charging infrastructure emerge as significant barriers limiting the adoption process. Discussion – The findings suggest that the motivations and barriers faced by Generation Z in the adoption of electric cars are important factors to be considered by policymakers and industry representatives. In line with the results of the study, various recommendations are presented for the future of electric vehicles. The study has limitations in terms of generalisability due to its limited geographical scope and participant diversity. This study provides important insights for future policy makers and industry representatives to consider when making strategic decisions.Bu çalışma 2209-A - Üniversite Öğrencileri Araştırma Projeleri Destekleme Programı kapsamında desteklenmiştir
Some Results on f-Statistical Convergence of Double Sequences
No full textThis study focuses on the development and examination of new definitions related to statistical convergence, modulus functions, and f?-density within 2-normed spaces. We investigate various relationships between statistical (f?-convergence, f?-statistical convergence, f?-statistically Cauchy sequences, f?-statistically bounded double sequences, and strongly f?s convergent double sequences in 2-normed spaces. Furthermore, we analyze certain topological properties connected to these concepts. © 2025 Elsevier B.V., All rights reserved
The effects of character strengths interventions on EFL adults' self-efficacy and willingness to communicate
No full textİnsan ve bu dünyadaki öz varlığı yüzyıllardır araştırmaların merak konusu olmuştur. Bilimin ve teknolojik gelişmelerin hız kazanmasıyla birlikte insan hayatı her geçen gün kolaylaşmış fakat mutlu olma durumu yerini daha çok mutsuzluğa bırakmıştır. Psikolojinin alt dallarından olan pozitif psikoloji de bu ihtiyaç sebebiyle geliştirilmiştir. Pozitif psikoloji, optimal insan işleyişi ve refahının bilimsel çalışmasıdır. Bireylerin ve toplumların gelişmelerine etki eden olumlu duygu, düşünce ve davranış kalıplarını incelemeyi amaçlayan bu alan, hastalık ve ruhsal rahatsızlıklardan daha çok insan zihninin sağlıklı yönlerine dikkat çekmektedir. İnsanların olumlu duygular ve davranış kalıpları geliştirerek hayatları boyunca mutlu yaşamalarını destekleyen ve bilimsel araştırma ve uygulamalarda pozitif olma durumunu önemseyen pozitif psikoloji, eğitim, sağlık, ekonomi, yönetim (örgütsel davranış), liderlik, sosyal hizmetler ve daha birçok alanda uygulanmıştır. Bununla birlikte, pozitif psikoloji müdahalelerinin yetişkinlerin doğal bir ortamda dil öğrenimi üzerindeki etkisini araştıran araştırma eksikliği vardır. Bu çalışmanın amacı, karakter güçleri müdahalelerinin İngilizceyi yabancı dil olarak öğrenen yetişkinlerin öz yeterlilik ve iletişim istekliliklerine etkilerini araştırmaktır. Araştırmada nicel ve nitel veri toplama yöntemlerini içeren karma araştırma yöntemi kullanılmıştır. Katılımcılar, 7 ders saati süresi boyunca bir dizi pozitif psikoloji karakter güçleri (yaratıcılık, merak, yargı, öğrenme aşkı, perspektif, öz denetim, liderlik) müdahalesine katılmışlardır. Bu süreç sonunda yabancı dilde öz-yeterlilik algıları İngilizce Öz Yeterlilik İnançları Ölçeği (Yanar ve Bümen, 2012) ile değerlendirilmiştir. Katılımcıların pozitif psikoloji müdahaleleri sırasındaki algıları, deneyimleri ve iletişim kurma istekliklerindeki değişiklikleri incelemek için ise yarı yapılandırılmış görüşme formu kullanılmıştır. Nitel veriler içerik analizi ile değerlendirilmiştir. Yapılan analizler sonucunda elde edilen bulgular, karakter güçleri müdahalelerinin, İngilizceyi yabancı dil olarak öğrenen yetişkinlerin öz yeterliliklerini anlamlı derecede etkilediğini ve iletişim istekliliklerini artırdığını göstermektedir. Çalışmanın sonunda araştırmacı ve eğiticilere yönelik öneriler sunulmuştur.For centuries, humans and their intrinsic existence have been subjects of curiosity in research. With the acceleration of scientific and technological advancements, human life has become increasingly easier, but the state of happiness has often been replaced by greater unhappiness. As a response to this need, positive psychology, a subfield of psychology, was developed. Positive psychology is the scientific study of optimal human functioning and well-being. This field aims to examine the positive emotions, thoughts, and behavior patterns that influence the development of individuals and societies, focusing more on the healthy aspects of the human mind rather than diseases and mental disorders. By supporting people in developing positive emotions and behavior patterns throughout their lives, positive psychology emphasizes positivity in scientific research and applications. It has been applied in various fields such as education, health, economics, management (organizational behavior), leadership, social services, and many others. However, there is a lack of research investigating the impact of positive psychology interventions on adult language learning in a natural environment. This study aims to explore the effects of character strengths interventions on the self-efficacy and willingness to communicate of adults learning English as a foreign language. The research employs a mixed-method approach, including both quantitative and qualitative data collection methods. Participants engaged in a series of positive psychology character strengths interventions (creativity, curiosity, judgment, love of learning, perspective, self-regulation, leadership) over seven class hours. At the end of this process, their perceptions of self-efficacy in the foreign language were assessed using the English Self-Efficacy Beliefs Scale (Yanar and Bümen, 2012). Additionally, semi-structured interview forms were used to examine participants' perceptions, experiences, and changes in their willingness to communicate during the positive psychology interventions. Qualitative data were evaluated through content analysis. The findings from the analysis show that character strengths interventions significantly impact the self-efficacy and willingness to communicate of adults learning English as a foreign language. The study concludes with recommendations for researchers and educators
Basalt Fiber Reinforced Polymers: A Recent Approach to Electromagnetic Interference (EMI) Shielding
No full textElectromagnetic wave (EMW) radiation pollution is getting more severe as result of the advancement of electronic technology. Researching shielding materials with superior EMI (electromagnetic interference) shielding characteristics is therefore crucial. Basalt fibers (BFs) have been an emerging candidate in the fiber-reinforced polymer (FRP) category due to their favorable mechanical and chemical properties, along with being favorites in sustainability and having low production costs. Therefore, due to the rising need for cheaper and efficient alternatives in the EMI shielding industry, the EMI shielding is covered in terms of BF composite materials and their properties in this review, starting with the EMI shielding mechanism and followed by how BF composites affect the EMI properties. This review then covers the post-treatments of BF composites and, finally, the factors of the composites that affect the EMI properties. Moreover, the EMI shielding applications in which BFRPs are used are comprehensively discussed as well. This review aspires to bridge an understanding between EMI shielding as a material property and the BF composites that are developed to aid in the EMI shielding application