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Düşük reynolds sayısında buz birikim etkisinin NACA 2415 kanat profilinin aerodinamik performansına etkisinin araştırılması
No full textLisansüstü Eğitim Enstitüsü, Havacılık ve Uzay Mühendisliği Ana Bilim Dalı, Havacılık ve Uzay Mühendisliği Bilim DalıBu tez, üç farklı buz birikiminin NACA 2415 kanat profilinin aerodinamik performansı üzerindeki etkilerini incelemektedir. Buzlanma ortamları, buzlanma türleri, buzlanmanın kanat profili ve uçak bileşenleri üzerindeki etkileri ve buzlanma önleme ve buz çözme teknikleri hakkında genel bilgiler verilmektedir. Re=1.2×105'te, ana kanat profilinin yanı sıra glaze buzlanma, rime buzlanma ve horn buzlanma oluşmuş kanat profilleri için deneyler gerçekleştirilmiştir. Bu çalışma için kuvvet ve hız ölçümleri ile yağ ve duman-tel akış görselleştirme teknikleri uygulanmıştır. Kuvvet ölçümleri için seçilen hücum açısı -7° ile 23° arasında değişmektedir. Ayrıca kuvvet ölçümleri sonuçlarından hız ölçümleri ve akış görselleştirme deneyleri için 0°, 4°, 8°, 13°, 14°, 17° ve 20° olmak üzere yedi farklı hücum açısı seçilmiştir. Sonuçlar, buzla birleşen kanat profillerinin CLmax değerinin beklendiği gibi azaldığını gösterdi. Maksimum kaldırma katsayısında GIA, RIA ve HIA modellerinde sırasıyla %20, %23 ve %88 oranında azalma gözlendi. GIA, RIA ve HIA kanat profilleri için ? = 0°'de sürükleme katsayılarındaki artış sırasıyla %14, %4 ve %307 idi. Stall sonrası GIA kanat profilinin kaldırma katsayısında ani bir artış gözlemlendi. Ayrıca hız ölçümlerinde GIA, RIA ve ana kanat profilleri için çift tepe davranışı kaydedilmiştir.This thesis examines the effects of three distinct ice accumulations on the aerodynamic performance of the NACA 2415 airfoil. A brief discussion is provided of icing environments, icing types and the icing effects on the airfoil and also on the aircraft components. Besides, some necessary information is provided for icing prevention (anti-icing) and de-icing techniques. The experiments are carried out for the base airfoil as well as glaze, rime, and horn ice accumulated airfoils at Re=1.2×105. For this study, force and velocity measurements are taken. Additionally, the oil and smoke-wire flow visualization techniques are also performed. The selected range of angle of attack for force measurements is defined as -7° to 23°. Additionally, considering the results of force measurements, seven distinct angles of attack values including 0°, 4°, 8°, 13°, 14°, 17° and 20° are chosen for velocity measurements and flow visualization experiments. Results showed that, CLmax of ice accreted airfoils are decreased as expected. 20%, 23% and 88% of decrease in maximum lift coefficient is observed in the GIA, RIA and HIA models, respectively. An increase in drag coefficients at ? = 0° for the GIA, RIA and HIA airfoils is observed to be around 14%, 4% and 307%, respectively. A sudden increase in lift coefficient of the GIA airfoil is observed at post-stall. Moreover, a double-peak behavior is noted for the GIA, RIA airfoil and also for base airfoil in velocity measurements
İçsel Yolculuklara Bellek ve Mekân Odaklı Bir Bakış: Kadından Kentler
No full textEdebî eserin önemli unsurları arasında yer alan mekân, kültürel kimlik ve bellek inşasında başat role sahiptir. Mekân ve insan arasındaki ilişkinin estetik düzlemde kurgusu, karakterlerin bireysel kimliğinin yanı sıra toplumsal kimliğe de ayna tutar. Murathan Mungan, kimlik ve belleğin inşa sürecini eserlerinde sıkça işleyen yazarlar arasında yer alır. Bu çalışmada Murathan Mungan’ın Kadından Kentler kitabındaki öyküler mekân ve bellek odağında bir yakın okumayla incelenmekte, toplumsal ve kültürel belleğin ışığında metin çözümlemesi yapılmaktadır. Öykülerde öznelerin mekânsal deneyimleri yolculuk metaforuyla aktarılırken onların kimliklerinde yaşanan değişim dikkate sunulur. Geçmişin derin izleri farklı mekân ve nesneler aracılığıyla yansıtılırken kadın öznelerin içsel yolculukları merkezdedir. Çalışmanın temel amacı, geçmişin travmatik deneyimlerine işaret edilen öykülerin mekân ve bellek odağında içerik analiziyle değerlendirilmesidir. Karakterlerin yer değiştirirken ev/yurt kavramına bakış açılarının şekillenmesi ve aidiyet duygusunda yaşanan değişim kentsel deneyimlerle ifade edilmektedir. Bu noktada kadın belleğinin inşa edilme sürecinde aidiyet, uyum ve süreklilik kavramlarına yüklenen anlamlar mekân ve eşyanın işleviyle bağlantılıdır. Kadın karakterlerin kimlik arayışları mekân-insan ilişkisi bağlamında irdelenirken öykülerde kültürel kimlik ve belleğe ait unsurların rolüne ışık tutulmaktadır
Antimicrobial topical polymeric films loaded with Acetyl-11-keto- ?-boswellic acid (AKBA), boswellic acid and silver nanoparticles: Optimization, characterization, and biological activity (vol 10, e31671, 2024)
No full text[Abstract Not Available
Exploring the Ecological Footprint in Turkey: Analyzing the Interplay of Economic and Environmental Factors
No full textNowadays, the world is facing increasing ecological issues due to the rapid growth of the population, the expansion of industrial activity, the fast urbanization process, and the higher levels of consumption. As a result of the current ecological problems, there has been an unchecked increase in the demand for natural resources. This study identified the independent variables that influence the ecological footprint as the Gross Domestic Product (GDP), KOF Globalization Index (KOFGI), and Natural Resource Rent (NRR). The Markov chains approach was used to anticipate the movements of the dependent and independent variables in the future period. Frequency and transition probability matrices were then generated. The dependent and independent variables for the next period were compared to the actual values, and the accuracy of the predictions made using Markov chains was demonstrated. A model of an Artificial Neural Network (ANN) was created to accurately predict the value of the dependent variable. The ANN modeling was used to estimate the ecological footprint, taking into account the values of Turkey's GDP growth rate (% per year), NRR (as a percentage of GDP), and KOF Globalization Index data from 1970 to 2016. The Feed-Forward Backpropagation Method, which is a type of multi-layer network model, was utilized for the modeling process. The Levenberg-Marquardt optimization algorithm was employed as the network training function to update the weight and deviation values of the network. The study's findings indicate that the dataset as a whole has a significant level of agreement with the model's correctness, with a close proximity of 99.316%. Based on the collected results, it can be inferred that the developed artificial neural network (ANN) model has a notable level of precision in calculating the Ecological Footprint
MARKET SEEKING OF AMERICA IN MERSIN IN THE LATE OTTOMAN PERIOD
No full textThe capitalist economy and industrial revolution developments, dominated the world conjuncture in the 19th century, formed the political infrastructure of European states. The gradual development of production technologies with the industrial revolution caused western countries to search for markets to sell manufactured goods and raw materials to put production technologies into practice. Commercial firms were marketing their products through intermediary firms or individuals by determining the target market they identified. They run a series of promotional campaigns to make the products or services of companies preferred by people. How these marketing techniques were used by American companies in Mersin, which was a quite new and open port to growth and demand in the late 19th and early 20th centuries, can be found in the letters of American Consulate. The knowledge about the marketing techniques applied by American companies, has been obtained from the letters of the American Consulate. The aim of the study is to reveal how the search for the market in Mersin, a port city, which was open to growth in the late 19th century and early 20th century, was carried out by these numerous American companies
Fabrication, characterization and antioxidant activities of pectin and gelatin based edible film loaded with Citrus reticulata L. essential oil
No full textIn the present work, pectin and gelatin-based edible films (EFs) loaded with Citrus reticulata L. (tangerine) essential oil were fabricated and evaluated for their potential application in food packaging. GC-MS analysis and physiochemical, mechanical, and antioxidant analysis of the synthesized edible films and oil extract were carried out. GC-MS analysis of the tangerine essential oil revealed the presence of around 40 different chemical constituents, and among them, limonene (43.85%), linalyl acetate (19.16%), linalool (18.38%), and beta-Myrcene (3.41%) were found as the major constituent. Fourier transform infrared spectroscopy showed the interaction between the functional groups of the film components. Mechanical parameter assessment showed that the tensile strength of the edible film increases and elongation at break values decreases with oil addition. The thickness of the EFs increased with oil addition, while water solubility, water vapor permeability, and transparency decreased. In antioxidant potential assessment assays, maximum activity (DPPH center dot and ABTS(center dot+) reducing potential) was reported for edible film samples containing a maximum amount (60 mu L) of tangerine oil. We found that pectin and gelatin-based edible films loaded with tangerine essential oil exhibit better characteristics and could be used as a food packaging material.TRC Oman; Natural and Medical Sciences Research Center, University of Nizwa OmanThe Authors are thankful to the Natural and Medical Sciences Research Center, University of Nizwa Oman, for providing research facilities to conduct the current study
Exploring the Impact of Infusion Parameters and In Vitro Digestion on the Phenolic Profile and Antioxidant Capacity of Guayusa (Ilex guayusa Loes.) Tea Using Liquid Chromatography, Diode Array Detection, and Electrospray Ionization Tandem Mass Spectrometry (vol 13, 694, 2024)
No full text[Abstract Not Available
Irritabl bağırsak sendromu ile ilişkili bağırsak mikrobiyotasinin tanımlanması
No full textLisansüstü Eğitim Enstitüsü, Biyomühendislik Ana Bilim Dalı, Biyomühendislik Bilim Dalıİnsan bağırsağında bulunan mikrobiyal gruplar arasındaki denge, sağlığın korunması için çok önemlidir. İrritabl bağırsak sendromu (IBS), kronik ve tekrarlayan karın ağrısı ve bağırsak alışkanlıklarında değişiklik gösteren yaygın bir sindirim bozukluğudur. Genetik, epigenetik ve cinsiyetle ilişkili faktörlerin sinir ve bağışıklık-endokrin üst sistemlerinin işleyişini etkilediği, ayrıca beyin-bağırsak fizyolojisinin düzenlenmesini, safra asidi üretimini ve emilimini etkilediği bilinmektedir. Bu çalışmanın amacı, IBS'li hastalarda bağırsak mikrobiyota çeşitliliğini araştırmaktır. Çalışma, mikrobiyal çeşitlilikteki değişikliklerin (düşük veya yüksek) IBS semptomları üzerindeki etkisinin yanı sıra hastaların sahip olduğu hastalıkların mikrobiyota ve IBS üzerindeki etkilerini belirlemeyi amaçlamaktadır. Balcalı Hastanesi'nde bir gastroenterolog tarafından kolonoskopi biyopsisi ile IBS hastalarından toplam 10 bağırsak örneği alınmış ve Illumina tabanlı yeni nesil dizileme yöntemleri kullanılarak bakteriyel biyoçeşitlilik analiz edilmiştir. IBS semptomları olan 10 hastadan alınan örnekler karşılaştırıldı ve semptomlar arasındaki ilişkileri yorumlamak için bakteri çeşitliliği analiz edildi.The balance of microbial communities in the human gut is critical to maintaining good health. Irritable bowel syndrome (IBS) is a common digestive disorder characterized by chronic and recurrent abdominal pain and altered bowel habits. Genetic, epigenetic, and gender-related factors are known to influence the function of the higher nervous and immune-endocrine systems, as well as the regulation of brain-gut physiology, bile acid production, and absorption. The objective of this study is to investigate the diversity of gut microbiota in patients with IBS. The study aims to determine the impact of changes in microbial diversity (low or high) on IBS symptoms, as well as the effects of diseases that patients have on microbiota and IBS. A gastroenterologist at Balcalı Hospital collected samples by colonoscopy biopsy, obtaining a total of 10 gut samples from IBS patients. Bacterial biodiversity was analyzed using Illumina-based next-generation sequencing methods. Samples from 10 patients with IBS symptoms were compared, and bacterial communities were analyzed to interpret the relationships between symptoms
The dark side of finance: the link between financialisation and labour investment in emerging Asian countries
No full textThis study explores the effect of financialisation on labour investment for emerging Asian economies. Focusing on firms operating in non-financial sectors, this study explores the financialisation-labour investment relationship for Hong Kong, South Korea, Taiwan, Indonesia, Malaysia, and India during the period from 1999 to 2023. This study employs a panel regression methodology to explore the link between financialisation and labour investment. The findings indicate that financialisation can exert a negative influence on the labour investment of manufacturing firms in these emerging Asian economies. The findings of the study are also not sensitive to different robustness checks. This paper sheds new lights on the effects of financialisation on labour investment within emerging economies
Online Contacts Supported with Recategorization Strategies: Do They Affect Outgroup Attitudes and Collective Action Intentions?
No full textStudies on face-to-face intergroup contact demonstrate varied effects for members of advantaged and disadvantaged groups on harmonious relations and collective action intentions. This study extends the literature by examining to what extent those effects exist when the contact is online and also by examining which recategorization strategy would be more effective in producing positive outcomes for those groups. For this aim, students of the two universities-CU and ATU (higher and lower status, respectively)-in Adana, Turkey were made to contact in small groups on a text-based online platform. Participants were distributed into four-people groups-either mixed of ATU and CU students or ATU students only. Either a common ingroup identity or dual identities were made salient in the mixed groups, whereas the individual identity was made salient in the groups consisting of ATU students only. Data were collected at three time periods: Two weeks before (368 participants), immediately after (159 participants), and one month after the contact (138 participants). Concerning outgroup attitudes, irrespective of salient identities, mixed groups improved attitudes, sustained in follow-up. Regarding collective action intentions, CU students' intentions increased (T1 to T3), while for ATU students in all groups, intentions decreased-whether cross-group contact was experienced or not