Sakarya University of Applied Sciences AXSIS
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Investigating the predictive role of reflective thinking and decision making on creative thinking dispositions
No full textThis study aimed to investigate whether university students' decision-making styles and reflective thinking skills are significant predictors of their creative thinking dispositions. The study was carried out with 245 university students and the data were collected with Marmara Creative Thinking Dispositions Scale, Reflective Thinking Scale, and Melbourne Decision-Making Questionnaire. This study revealed that university students presented high creative thinking dispositions and reflective thinking skills as well as high decisional self-esteem. Also, most of them use vigilance as a decision-making style. Besides, reflective thinking skills, decisional self-esteem, and vigilance decision-making style were positively correlated to creative thinking dispositions while buck-passing, procrastination, and hyper-vigilance decision-making styles were negatively correlated to creative thinking dispositions. This study also showed that university students' reflective thinking skills, decisional self-esteem, and decision-making styles significantly predicted their creative thinking dispositions, and 18% of the total variance on their creative thinking dispositions was explained by reflective thinking skills and decision-making styles
Drought analysis and trend evaluation of the basins of the Mediterranean Region
No full textKuraklık, belirli bir coğrafi bölge sınırları içinde uzun süre normal yağış miktarının altında seyrettiği meteorolojik bir durum olarak tanımlanmaktadır. Bu durum, su kaynaklarında azalması, tarımda verimliliğin düşmesi, ekosistemlerde dengesizliklerin oluşması ve su sıkıntısı gibi çeşitli etkilere neden olmaktadır. Kuraklık, doğal koşullarla birlikte insan faaliyetlerinin etkisiyle de ortaya çıkmakta veya şiddetlenebilmektedir. Yağış rejimi, toprağın nem oranı, bitki örtüsü ve su kaynakları gibi belirleyici faktörlerin incelenmesiyle kuraklık analizi yapılmaktadır. Bu analiz, kuraklık riskinin belirlenmesine ve etkilerinin önceden tahmin edilmesine yardımcı olmaktadır. Bu tez çalışmasında, Akdeniz Bölgesi'nde yer alan havzalarda kuraklık analizi ve trend değerlendirmesi gerçekleştirilecektir. Bu çalışmada, yaşamımızı önemli ölçüde etkileyen değişkenlerden biri olan toplam yağış miktarı ve ortalama sıcaklık verileri kullanılarak kuraklık analizi üzerine odaklanılmıştır. Bu verilerin temini Meteoroloji Genel Müdürlüğünden sağlanmıştır. Analizler için 1989 ile 2022 yılları arasında toplam 34 yıllık veri kullanılmıştır. Bu veriler, 43 farklı noktada bulunan meteorolojik istasyonlar tarafından kaydedilmiştir. Ancak verilerden en uygun 9 istasyon seçilmiş. Verilerin trend değerlendirmesi yapabilmek için, Mann-Kendall, Spearman's Rho, Sen's Slope, yenilikçi yöntemlerin en yenisi olan CETA yöntemi ve ilk kez bir tez çalışmasında kullanılacak olan Double IPTA kullanılmıştır. Çalışma sonucunda, Double IPTA yöntemi diğer yöntemlerle karşılaştırıldığında, CETA ve Sen's Slope yöntemi ile uyumlu olduğu görülmüştür. Diğer yöntemler ile farklılıklar gösterdiği görülmüştür. Analiz sonucunda, yağış verilerinin %4'ünde trend olmadığı, %46'sında azalan trend olduğu ve %50'sinde artan trend olduğu sonucuna varılmıştır. Sıcaklık verilerinin %3'ünde trend olmadığı, %27'sinde azalan trend olduğu ve %70'inde artan trend olduğu sonucuna varılmıştır. Kuraklık verilerinin %2'sinde trend olmadığı, %51'inde azalan trend olduğu ve %47'sinde artan trend olduğu sonucuna varılmıştır. Çalışma sonucunda, sık ve şiddetli kuraklık olaylarının yaşanabileceğine işaret etmektedir. Bununla birlikte artan nemlilik trendi, ani kuraklık koşullarına dönüşmesini ve bu durumun ekosistemlerdeki dengesizlikleri ifade ettiğini göstermektedir. Bu durum, su kaynaklarında azalması, tarımda verimliliğin düşmesi, turizmin azalması, ekosistemlerde dengesizliklerin oluşması ve su sıkıntısı gibi çeşitli etkilere neden olabileceği sonucuna varılmıştır
Theoretical comparison analysis of R134a, R1234yf, R452A and R454C refrigerants used in automobile, trailer and commercial and industrial cooling systems
No full textThe increasing environmental disasters in recent years are caused by the release of artificial substances into the environment. The majority of artificial-containing emissions originate from petrochemical products. It also contributes to artificially containing refrigerants used in cooling systems. Artificial refrigerants have contributed greatly to the depletion of the ozone layer and subsequently to global warming. Research on new refrigerants as an alternative to refrigerants that contribute to every environmental disaster is of great importance. In this study, theoretical performance comparisons were made between R1234yf, which is an alternative to R134a refrigerant used in automobile air conditioning systems, and R452A, R454C refrigerants, which are used as alternative refrigerants in industrial, commercial and trailer cooling systems. Performance analyses were carried out according to different condenser and evaporator temperatures. Analysis results are given depending on condenser/evaporator pressure ratio, mass flow rate, compressor power, cooling effect coefficient (COP) and compressor outlet temperature. According to the study results, it was observed that the COP value increased with the increase in evaporator temperature, while the compressor inlet-outlet pressure ratio, refrigerant flow rate, compressor power and refrigerant compressor outlet temperature decreased. It was observed that the refrigerant with the highest compressor power and mass flow rate was R452A, followed by R1234yf, R454C and R134a, respectively. R134a was found to have an average of approximately 5.4%, 8.6% and 0.6% higher COP than R1234yf, R452A and R454C, respectively
Dry Friction and Wear of Graphite-Filled PTFE Composites using Taguchi Approach
No full textComposite plain-bearing specimens with a porous structure were produced from spherical bronze powders (100–200 µm) using sintering technology. Pure Polytetrafluoroethylene (PTFE) and PTFE composites were then impregnated into the porous bronze structure and coated onto the surface. The PTFE mixtures were reinforced with graphite particles, with the graphite powder (average particle size: 200 µm) incorporated into the PTFE solution at varying ratios. This process was applied using the spray coating technique. Wear experiments were conducted based on a design created using the Taguchi method. The experimental parameters were optimized using the L27 Taguchi orthogonal array to achieve optimal friction coefficient and wear loss. The results showed that the experimental and verification test results were highly consistent. The material type/graphite content had the most significant impact on the friction coefficient and wear loss (71.6% and 30.88%, respectively). Sliding speed had the greatest effect (55.06%) on bearing temperature. Elemental analysis and chemical characterization of the composite plain bearing specimens were conducted using Energy Dispersive Spectroscopy (EDS). The wear surfaces were examined via Scanning Electron Microscope (SEM).The study concluded that the most significant factor affecting bearing wear is the material type. The 10% graphite additive, which reduces friction in the material, yielded optimal results in the study. An increase in sliding speed leads to a rise in bearing temperature, which in turn accelerates wear. Compared to industrially used bearings, the study found that more graphite lubricant was impregnated into the pores of bronze, and the optimal 10% additive provided a positive advantage in wear performance. © 2024 National Institute of Science Communication and Policy Research. All rights reserved
Production and development of ZnAlGeO semiconducting materials for thermoelectric generators in potential aerospace applications
No full textThis research aims to produce and develop semiconducting thermoelectric materials for thermoelectric generators in aerospace applications. In this context, ZnAlGeO powders were synthesized via the sol-gel method using precursor materials and a 20% toluene solution in ethanol as the solvent. Glacial acetic acid was added to accelerate gel formation. The pH and turbidity values of prepared solutions were measured using a pH meter and turbidimeter. After gelation, the obtained xerogel was dried at 200 °C for 9 h to remove moisture and undesired gases. Dried powders were calcined at 600 °C for 4 h in air, resulting in final ZnAlGeO materials. The pellets underwent thermal processing for 36 h at a temperature of 1350 °C, targeting the production of bulk samples within the n-type semiconductor category. Extensive characterization, including thermal, structural, microstructural, and thermoelectric properties, was conducted using various techniques such as DTA-TG, FTIR, XRD, XPS, SEM, and thermoelectric measurement devices. The study concludes that the produced semiconducting ceramic materials exhibit efficiency for thermoelectric generator production. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024
Evaluation of Clinical Course and Outcomes of Severe Sepsis and Septic Shock in Elderly Patients
No full textObjective: Our objective was to prospectively evaluate patients with sepsis and septic shock in terms of their clinical course, laboratory findings, risk factors, treatment options, and prognosis. We also compared data among the elderly (≥65 years) and non-elderly (<65 years) patients with severe sepsis and septic shock. Materials and Methods: The study was a single-center prospective observational study conducted between 2014 and 2017. All adult patients with sepsis and septic shock hospitalized in the medical intensive care unit (ICU) and Infectious Diseases Department were included in the study. Results: This analysis included 250 patients admitted with severe sepsis or septic shock. Elderly patients accounted for 60.0% (150/250) of the patients. In logistic regression analyses of risk factors, elderly patients with sepsis and septic shock were more likely to have a higher odds ratios (ORs) for smoking (OR=3.658 [1.988-13.538], p=0.050), medication use (OR=5.365 [1.943– 30.524], p=0.048), underlying diseases (OR=2.023 [1.333–12.292], p<0.001), hyperglycemia (OR=14.448 [2.690–77.612], p=0.002), multiple organ dysfunction syndrome (MODS) (OR=293.998 [2.247–53.713], p=0.001), and Charlson Comorbidity Index (CCI) (OR=1.301 [1.057– 1.600], p=0.013). Conversely, non-elderly patients with sepsis and septic shock were more likely to have higher ORs for body mass index (BMI) (OR=0.789 [0.700–0.911], p=0.001), chronic renal failure (OR=37.076 [5.374–255.811], p<0.001), hematological malignancy (OR=84.348 [10.661– 667.375], p<0.001), and leucopenia (OR=86.374 [6.622–1126.577], p=0.001). Conclusion: Elderly patients with sepsis and septic shock are more susceptible to multiple organ failure. While sepsis was not associated with increased mortality in this study, targeted early interventions may be effective in reducing mortality in older patients and in managing chronic diseases
A Comprehensive Density Functional Theory Analysis on Structural, Electronic, and Optical Properties of BiOF
No full textBased on density functional theory (DFT), the electronic, structural, and optical properties of bismuth oxyfuoride (BiOF) are investigated by using various exchange–correlation functionals. The local density approximation (LDA), Perdew-BurkeErnzerhof generalized gradient approximation (PBE-GGA), Perdew-Burke-Ernzerhof generalized gradient approximation for solids (PBEsol), and Wu-Cohen (WC) functionals are implemented in Wien2k software. Modifed Becke-Johnson (mBJ) and unmodifed Becke-Johnson (umBJ) potentials are also applied to obtain an enhanced band gap. Spin–orbit coupling efect (SOC) is also taken into consideration due to the heavy Bi atom. When employing the PBE+umBJ potential, BiOF exhibits the most enhanced band gap energy, with a direct band gap energy of 3.72 eV. Moreover, optical properties such as dielectric functions, absorption coefcients, and optical conductivities are also calculated for photon energies up to ̴ 14 eV. In comparison to other available theoretical and experimental fndings, the calculated results are in good agreement
Farklı Kimyasal Yöntemlerle Kaplanmış Çelik Plakaların Farklı Yapıştırma Kalınlıklarda Tek Bindirmeli Birleştirme Yöntemiyle Birleştirilen Numunelerin Yorulma Analizleri Sonuçlarının Wöhler Eğrilerinde Karşılaştırılması
No full text18. yy. ikinci yarısında başlayan endüstri devriminden günümüze kadar yaşanan teknolojik gelişmeler içinde malzeme teknolojisinin günden güne gelişmesiyle bu malzemelerin birleştirme yöntemleri de geliştirilmektedir. Bu yöntemlerden biri de son 40 yıldır gelişme gösteren yapıştırıcı kimyasalların başarıyla kullanıldığı yapıştırma metodudur. Özellikle günümüzde otomotiv firmalarının araçlarının ağırlıklarını hafifleştirilme eğilimi arttığı için farklı türdeki ve düşük yoğunluktaki malzemelerin birleştirilmesinde alternatif olarak yapıştırıcı elemanının kullanıldığı Kimyasal Birleştirme Metodu hemen hemen her sektörde başarıyla kullanılmaktadır. Bu çalışmada, otomotiv sektöründe sac kaplamada sıklıkla kullanılan DC01A soğuk haddelenmiş çelik malzemenin doğal yüzeyine ilaveten astar boya ve kataforez kaplama olarak farklı kimyasal kaplama metotları uygulanmış olup, poliüretan bazlı bir yapıştırıcı elemanıyla farklı kalınlıklarda çelik numuneler birleştirilmiştir. Bu çalışmanın amacı, yapıştırıcı ile birleştirilen iki çelik malzemenin yapıştırıcı elemanın hangi kalınlıkta ve hangi kaplama metodunun yüzeyinde güçlü ve esnek bir bağ oluşturduğunu araştırmaktır. Araştırma metodu olarak numunelere yorulma testleri uygulanmıştır. Yorulma testi sonucunda 3 mm yapıştırıcı kalınlığındaki kataforez kaplı numune 0,05 MPA gerilimde sonsuz ömre sahip olurken, diğer numuneler ömür testinde başarısız olmuştur. Yorulma testleri sonucunda elde edilen Gerilim (S) ve Çevirim (N) verileriyle Wöhler eğrileri oluşturarak sonuçlar değerlendirilmiştir. Sonuç olarak, uygulanan testler sonuçlarında 3 mm.’ye kadar yapıştırma kalınlığında ve kataforez kaplı numuneler, astar boyalı numunelere göre daha iyi yapışma performansı sağlandığı tespit edilmiştir. Yüzeyinde kaplama olmayan numunelerin birleştirilmesinde yeterli dayanım elde edilememiştir
LOOKING AT SOCIAL MEDIA AND STATES OF ALIENATION THROUGH THE PHOTOS OF ERIC PICKERSGILL AND MARTIN PARR
No full textSmart devices, which increase the dominance of people in their daily lives, are becoming a part of life with the proliferation of social media platforms. The normalization of human images, which are isolated from the time and place they are in and focus only on the screen in front of them, in public transportation vehicles, stops and visits to relatives, summarizes this situation. Eric Pickersgill strikingly reflects these states in his photographic project Removed. The images that Pickersgill produced by blurring smart devices from their framing arouse curiosity as to whether similar situations were experienced before smart devices were invented. The main aim of the study is to examine the situations of isolation, which are frequently encountered in the social media age, in the context of alienation through Eric Pickersgill's photographs and to compare this project with Martin Parr's photographic project called Bored Couples and to question whether alienation has been experienced before the invention of smart devices. Photo projects selected with purposeful sampling were analyzed by document analysis method and compared in the context of Marx's social approach to alienation. As a result of some remarkable similarities between the photographs, important clues have been reached that the states of isolation before and during the social media age can be associated with the alienation of the individual from himself and his environment
Psychometric Property Examination of a Self-Assessment Fear Scale in Turkish Children Aged 4–12 Years: A Methodological Study
No full textBackground: Given the lack of validated tools to assess fear in Turkish children, this research aims to address this gap by conducting a methodological study to examine the validity and reliability of the Fear Scale, thereby providing health care professionals and researchers with a reliable instrument to evaluate fear levels in this population. Methods: The research was conducted on 150 children aged 4–12 years and their parents who applied to the pediatric blood collection unit of Koç University Faculty of Medicine Hospital. In the study, the “Sociodemographic Characteristics Form,” “Fear Scale,” and “Child Fear Scale” were used for data collection. Results: A very high statistically significant positive relationship was obtained between the Fear Scale and the Child Fear Scale (r = .973; p < .001). The high correlation value between the two forms indicates that the child form is valid. The content validity index and item content validity index values of the scale were found to be 0.98. A very good level of statistically significant agreement was achieved between the Fear Scale and the Child Fear Scale (κ = .878; p < .001). Conclusion: It was found that the Turkish psychometric properties of the Fear Scale are valid and reliable for children aged 4–12 years. It is suggested that pediatric nurses use the scale in clinics to evaluate their fear about procedural operations. © 2024 Springer Publishing Company