Effect of Gr Contents on Wear Properties of Al2024/MgO/Al2O3/Gr Hybrid Composites

In the present study, hybrid metal matrix composites, Al2024/10Al2O3, Al2024/10Al2O3/3MgO, Al2024/10Al2O3/6MgO, Al2024/10Al2O3/3MgO/1.5 Gr, Al2024/10Al2O3/3MgO/3Gr, and reinforcement samples (AA 2024) produced with powder metallurgy process. AA 2024 and reinforcement powders were determined mixture rations and separately mixed during 30 minutes in a three-dimensional Turbula mixer. The mixed compositions were pressed at 300 MPa and sintered at 550°C during 1 h. After that, three materials were extruded at the same temperature. Experimental results show that hybrid metal matrix composites (HMMCs) a better wear resistance than the reinforcement samples because of higher hardness. Gr behave as a lubricant during wear process. The wear resistance of HMMCs can be optimized with controlling of the reinforcement content and type. © 2018 The Authors

Investigation of the effect of 12-week exercise training on the level of physical fitness in children with autism

The aim of this study is to investigate the effect of 12-week exercise training on the level of physical fitness in autistic children. A total of 10 individuals, 4 females and 6 males, residing in Çanakkale city center and having autism are included in the study. The age range of individuals participating in the study is 13-19. These individuals were reached through previous volunteer projects and Kepez Special Education Vocational School. Studies were conducted 2 days a week, Monday - Thursday, for 12 weeks. The studies were conducted between 40 and 55 minutes, depending on the content of the study. Particular attention was paid to the safety and health aspects of the studies. Students studying at the Faculty of Sports Sciences supported the studies voluntarily. Various tests are used to scale the physical parameters as a data collection tool in the study. In the analysis of the data, normality test and reliability test results were examined and it was determined that the data conformed to normal distribution wand was reliable. Based on this point, parametric testing techniques were used to test the data. Differences between pretest and posttest mean values were performed using Paired Groups T Test. According to the results obtained, it is concluded that there is no statistically significant difference between the height, weight, flexibility, biceps, triceps, suprailiac and suspcapula pre-test and post-test mean values of the male and female participants

Yeni rekabet koşullarında işletmeler ve stratejik yönetici yetenekleri

The purpose of this article is to determine as a whole the strategic firm capabilities required by the new competition conditions and the main managerial capabilities which may bring the strategic capabilities to the firm; therefore to contribute to the related literature. For this purpose, the main approaches for developing strategies that would bring competitive advantages to the firms and the ‘firm capabilities’ concept have been investigated. The capabilities descriptions in the literature have been analyzed and categorized successively. In addition, the major types of capability, the strategic firm capabilities required by the new competition conditions, together with their relations and organizational conditions required in the firms have been determined. At the end of the study, a model showing main managerial capabilities which may bring the strategic and organizational capabilities to the firm and their relations with each other have been proposed.Bu çalışmanın amacı, yeni rekabet koşullarının gerektirdiği stratejik işletme yeteneklerini ve bu yetenekleri işletmeye kazandırabilecek başlıca yönetsel yetenekleri bir bütün olarak ortaya koymak; ilgili literatüre katkıda bulunmaktır. Bu amaçla, işletmelere rekabet avantajı sağlayacak strateji belirleme yaklaşımları ve işletme yetenekleri kavramı incelenmiştir. Literatürdeki yetenek tanımları analiz edilip gruplandırılmıştır İşletmelerdeki başlıca yetenek türleri, yeni rekabet koşullarının gerektirdiği stratejik yetenekler, bu yeteneklerin birbiriyle etkileşimleri ve gerektirdiği örgütsel koşullar belirlenmiştir. Çalışmanın sonunda, İşletmelere stratejik yetenekleri kazandırmada etkili olabilecek başlıca yönetsel yetenekleri ve birbiriyle etkileşimlerini gösteren model önerilmiştir

Foreign Capital, Real Sector Financing and Excessive Leverage in Turkey: What Went Wrong?

Recently, large swings in inflation and exchange rates revealed that non-financial sector is heavily geared and extremely vulnerable. Therefore, a study trying to identify the contributing factors is needed. Separating firms into groups, based on size and stock market trading status; changes in financing patterns are investigated via panel data methodology. The study aims at fulfilling the need for analyzing the consequences of foreign capital flow at firm level and documenting its significance in addition to assessing the efficacy of contemporary monetary policy. Economic conditions significantly facilitated lending process, strengthening corporate access to credit, and resulted in excessive borrowing both in the form of foreign and domestic currency. With such heavy burden of debt, non-financial sector has been facing both exchange rate and the liquidity risks. The more severely a firm was previously challenged by financing limitations, the more it borrowed once the limitations are relaxed, contributing to excessive debt burden of the economy in proportion to its previous financing challenges

Context Dependency of Community Dynamics: Predator-Prey Interactions Under Ecological Disturbances

Numerous studies have focused on the drivers of diversity and stability of communities, especially under global change. However, multi-dimensionality of ecosystems due to biotic components (e.g predation, competition and adaptive dynamics) and abiotic factors (e.g. disturbances, resource dynamics and their distinct attributes) cause context-dependent outcomes and challenge the predictions. There are still controversies around complex community dynamics under varying regimes, however, finding mechanistical explanations will illuminate the fate of multispecies assemblages. Using model microbial communities, consisting of bacterial prey and protist predator, combined with simulation modelling and advanced statistics, this thesis investigated the impact of imposed disturbances (i.e. increased dilution rates that simulate density-independent mortality as press or pulse disturbances) (i) on transient recovery dynamics of a simple microbial food web, and (ii) on bacterial abundance, diversity and community structure in the absence or presence of a protist predator. In addition, this thesis questioned the impacts of species interactions and rapid trait shifts, as a response to predation and competition, on the community dynamics and stability. Our results revealed that the predator suffered more from disturbances over longer time periods. Reduced predation pressure caused a transient phase of prey release during and even after disturbances. Recovery time depended on the strength and duration of disturbances, however, coupling to an alternative resource increased the chance of fast recovery and stabilized the communities. In multi-species prey communities, bacterial abundance, diversity, and community composition were more affected by predation than by the disturbances and resource dynamics. Predator abundance, on the other hand, was strongly affected by the type of disturbance imposed. Importantly, community attributes had differential sensitivities, as reflected by their different response and recovery dynamics. Prey community dynamics varied more temporally andwere less stable under predation stress, while prey diversity increased significantly. Predation rapidly induced anti-predation traits, which altered population dynamics of both prey and predator. More importantly, predator and the resistant prey, in turn, elevated the number of direct cause-effect relationships between the community members. Our findings are not limited to the studied system and can be used to understand the dynamic response and recovery potential of many natural predator-prey or host-pathogen systems. They can be used as a base for future studies to illuminate the debates on the future communities.:Summary Zusammenfassung 1 Scope and Outline 2 General Introduction 2.1 Context dependency of community dynamics 2.2 Ecological disturbances 2.2.1 Transient dynamics and stability 2.2.2 Catastrophic shifts 2.3 Species interactions and evolutionary dynamics under environmental change 2.3.1 Species interactions and coexistence 2.4 Eco-evolutionary dynamics 2.5 Community assembly mechanisms 2.6 Dealing with complexities 2.6.1 Microbial model systems as a tool in ecology 2.6.2 Correlation, causation and the future of predictions 2.7 Aims of this study 3 Community Dynamics under Disturbances 3.1 Transient recovery dynamics of a predator-prey system 4 Interactions of Community Drivers 4.1 Interactions between predation and disturbances shape prey communities 5 Species Interactions and Evolutionary Dynamics Shaping Communities 5.1 Summary 5.2 Introduction 5.2.1 Predator-Prey Dynamics and Community Stability 5.2.2 Causal inferences 5.3 Aim of the study 5.4 Methods 5.4.1 Organisms 5.4.2 Microcosm experiments and estimation of species abundances 5.4.3 Statistical analysis 5.5 Results 5.5.1 Community dynamics 5.5.2 Dynamics of prey diversity and community stability 5.5.3 Causal links between the species dynamics 5.6 Discussion 5.7 Synopsis 6 General Discussion 6.1 Communities under disturbances: Predator{ prey dynamics 6.2 Temporal species dynamics and community assembly Synthesis and Outlook 7.1 Increasing complexity of species interactions 7.2 Going further from causal links 7.3 Metacommunities References 8 Appendix 8.1 Declaration of the authorship 8.2 Author contributions of published articles 8.3 List of publications and conference contributions 8.4 Acknowledgments 8.5 Supplementary material for Chapter 3 8.6 Supplementary material for Chapter 4 8.7 Supplementary material for Chapter

Öğrencilerin Fen Okuryazarlığı Performanslarının Aşamalı Doğrusal Modelleme ile İncelenmesi: PISA 2015 Türkiye ve Singapur Karşılaştırması

This study aimed to investigate the extent to which variables directly related to science, which are found in the Programme for International Student Assessment (PISA) 2015 survey predicted the science literacy performance of students in Turkey and Singapore samples and determine the differences and similarities between the samples of the two countries. The study used the relational screening model. The study sample consisted of a total of 9680 students at the age of 15, which included 4643 students from the Turkey sample and 5037 students from the Singapore sample. Also, the sample included 177 schools from Turkey and 163 schools from Singapore. The study used the Hierarchical Linear Modeling (HLM) statistical technique, which is appropriate for hierarchical data because the school and student-level variables were together in the study. According to the findings of the study, science literacy performance indicated a significant difference between schools for both countries. However, approximately 52% of the difference in students' science literacy scores for Turkey sample and 34% for Singapore sample were found to stem from differences between schools. Student-level interest in science, research-based science teaching and learning practices, teacher support in science lessons, science self-efficacy, teacher-centered science teaching variables, and the proportion of science teachers at school level were determined to be a significant predictor of science literacy in both countries. However, the variables which are the significant predictors of science literacy were found to be "the enjoyment of science" for Turkey and "the disciplinary climate in science courses" variable for Singapore. On the other hand, the proportion of science teachers with an undergraduate education of four years or more, which is one of the school-level variables, was found to be not a significant predictor of science literacy performance fro both countries.Bu araştırma ile Uluslararası Öğrenci Değerlendirme Programı (Programme for International Student Assessment-PISA) 2015 uygulamasında yer alan doğrudan fene yönelik değişkenlerin, öğrencilerin fen okuryazarlığı performanslarını yordama durumlarının uygulamaya katılan Türkiye ve Singapur örneklemleri üzerinde incelenmesi ve iki ülke örneklemi bakımından benzerlik ve farklılıkların belirlenmesi amaçlanmaktadır. Araştırmanın modeli ilişkisel tarama modelidir. Araştırma örneklemi, Türkiye örnekleminden 4643, Singapur örnekleminden 5037 olmak üzere toplam 9680 onbeş yaş grubu öğrenciden oluşmaktadır. Bununla birlikte Türkiye‘den 177, Singapur’dan 163 okul araştırma kapsamında incelenmiştir. Araştırmada okul ve öğrenci düzeyinde değişkenler bir arada yer aldığından hiyerarşik verilere uygun olan Aşamalı Doğrusal Modelleme (Hierarchical Linear Modeling-HLM) istatistik tekniği kullanılmıştır. Çalışmadan elde edilen bulgulara göre fen okuryazarlığı performansı her iki ülke için de okullar arasında anlamlı bir şekilde farklılaşmaktadır. Bununla birlikte öğrencilerin fen okuryazarlığı puanlarındaki farklılığın Türkiye için yaklaşık %52'si, Singapur için %34'ü okullar arası farklılıktan kaynaklanmaktadır. Öğrenci düzeyinde fene yönelik ilgi, araştırmaya dayalı fen öğretimi ve öğrenme uygulamaları, fen dersinde öğretmen desteği, fen özyeterliliği, öğretmen odaklı fen öğretimi değişkenleri ve okul düzeyinde fen öğretmeni oranı her iki ülke için de fen okuryazarlığının anlamlı bir yordayıcısı olarak belirlenmiştir. Bununla birlikte Türkiye için yalnızca fenden keyif alma değişkeni, Singapur için ise fen dersinde disiplin iklimi değişkeni fen okuryazarlığının anlamlı bir yordayıcısıdır. Okul düzeyi değişkenlerinden 4 yıl ve üzeri eğitim almış fen öğretmeni oranı ise her iki ülke için fen okuryazarlığı performansının anlamlı bir yordayıcısı olmadığı ortaya konulmuştur

Listening Skills Development in Teaching Turkish as a Foreign Language and The Usage of Metacognitive Strategies

The aim of this study is to determine the state of using metacognitive strategies to develop listening skills in teaching Turkish as a foreign language to Syrian children. This research is a descriptive study designed with the survey method. In June 2017, the Certification Program for Teaching Turkish as a Foreign Language was organized for Turkish educators who work in Adana, as a part of “The Project of Supporting Syrian Children’s Integration into the Turkish Education System”. In this context, all Turkish educators who work in Adana composed the population of this study while 108 Turkish educators constituted the sample of the study. In this study, the data were collected by the “Metacognitive Listening Strategies Opinion Form” developed by the researcher and analyzed with descriptive statistical techniques.  The findings of the study showed that most of the metacognitive strategies that can be used before listening are rarely used and that the response rates as to “always” or “often” in the questionnaire are quite low. It was observed that Turkish educators usually “rarely” used strategies apart from the strategy of “underlining words the meaning of which they do not know” in the listening process.The findings further indicated that more strategies were used before and after listening than during listening and that the most frequently used strategies by learners were summarizing the listening text in their own words, expressing the theme and main idea of the text they were listening to, telling which section/s in the listening text they mostly focused on, and answering the listening comprehension questions

THE OPINIONS OF THE STUDENTS OF THE MUSIC DEPARTMENT ABOUT THE EDUCATION PROCESS DURING THE COVID-19 PANDEMIC

The Covid-19 pandemic, which began in Wuhan, China in 2019 and has impacted the world, has led to mandatory changes in all areas, particularly in the health sector. There is no doubt that education is one of the areas that has been impacted by the pandemic process and has faced rapid change. The purpose of the study was to determine the opinion of music department students on the education process during the Covid-19 pandemic, which began to take effect in our country in March 2020. The study group that conducted the research is composed of fourth-year undergraduate students studying at the College of Art, Design and Architecture, Department of Music in Çankırı Karatekin and Düzce Universities. The data of the study, which was carried out using document review and interview methods, which are qualitative research methods, were collected using a semi-structured interview form and analyzed with content analysis. As a result of the study, many important findings have been reached such as that the students of the music department have problems related to the physical space and facilities arising from being with the family, that they feel serious deficiencies in the quality of the education they receive in this process, that their professional self-confidence is damaged, and that there are losses in their psychological and physical health