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Investigating the External Impacts on Public Affairs Education in Türkiye: Getting a Ph.D. Degree Abroad Türkiye'de Kamu Yönetimi Eğitimi Üzerindeki Dışsal Etkilerin İncelenmesi: Yurt Dışında Doktora Derecesi Almak
No full textExamining the developmental rotation of public affairs education in Türkiye cannot be adequately undertaken solely through a single policy lens within the framework of national higher education and administrative reform policies. Instead, a more nuanced approach entails delving into the discipline's specific structural and contextual evolution through external impacts. This study focuses on a special type of external impact: faculty members receiving their Ph.D. degrees abroad. The purpose of the study is to investigate the impact of obtaining a Ph.D. degree abroad on public affairs education in Türkiye and to reveal the enablers and barriers of this process by focusing on the experiences of those faculty members. Through the interviews conducted with 24 faculty members who received their Ph.D. degrees abroad and came back home, the findings suggest that such an external impact has the potential to be as effective as any other higher education policy. Yet, this process faces some internal barriers, tension points, and enabling factors
Collision-Free Nonlinear Model Predictive Control for Quadrotors in Dynamic Outdoor Environments
No full textEnsuring safe and efficient navigation of quadrotors in dynamic outdoor environments requires accurate prediction of obstacle motion and adaptive collision avoidance strategies. This paper proposes a Nonlinear Model Predictive Control (NMPC) framework that integrates an Interacting Multiple Model Kalman Filter (IMM-KF)-based motion prediction scheme to enhance dynamic obstacle avoidance. The IMM-KF concurrently evaluates multiple motion models and probabilistically merges their estimates, enabling robust and adaptive predictions of obstacle trajectories under varying dynamic conditions. To further enhance obstacle avoidance, an uncertainty-aware repulsive potential field term is incorporated into the NMPC cost function, dynamically adjusting the repulsion force based on prediction confidence. This formulation enables smoother navigation and reduces abrupt maneuvers, enhancing reliability. The proposed approach is evaluated in simulated outdoor environments with static and dynamic obstacles, showing improved trajectory tracking, obstacle avoidance, and robustness to sensor noise and motion uncertainty. These results demonstrate the framework's effectiveness and real-time suitability for complex, uncertain environments
32-bit and 64-bit CDC-7-XPUF Implementations on a Zynq-7020 SoC
No full textPhysically (or Physical) Unclonable Functions (PUFs) are basic and useful primitives in designing cryptographic systems. PUFs are designed to facilitate device authentication, secure boot, firmware integrity, and secure communications. To achieve these objectives, PUFs must exhibit both consistent repeatability and instance-specific randomness. The Arbiter PUF (APUF), recognized as the first silicon PUF, is capable of generating a substantial number of secret keys instantaneously based on the input, all while maintaining a lightweight design. This advantageous characteristic makes it particularly well-suited for device authentication in applications with constrained resources, especially for Internet-of-Things (IoT) devices. Despite these advantages, APUFs are vulnerable to machine learning (ML) attacks. Hence, those APUF designs were improved to achieve increased resistance against such attacks while maintaining usefulness and efficiency for IoT applications, and Component-Differentially Challenged XOR Arbiters (CDC-XPUFs) were proposed. In this work, ML-resistant 32-bit and 64-bit implementations of the Component-Differentially Challenged XOR Arbiter PUF with 7-stream (CDC-7-XPUF) are carried out. These CDC-7-XPUFs are evaluated using PUF metrics from the literature, and the resource utilization ratios of both implementations are also presented. The implementation setup contains the ZC702 Rev1.1 Evaluation Board, featuring the Xilinx Zynq-7020 SoC, and utilizes a configuration involving three boards for experimental validation
Sınıf Öğretmenlerı̇nı̇n Temel Motor Becerı̇lerı̇n Öğretı̇mı̇ne İlı̇şkı̇n Algıladıkları Bı̇lgı̇ ve Uygulamalar ile Öğrencı̇lerı̇n Motor Yeterlı̇klerı̇: Uygulama Temellı̇ Meslekı̇ Gelı̇şı̇m Programı
No full textThe study aims to (1) investigate the changes in classroom teachers’ experiences related to the teaching of FMS, (2) determine the proportion of teachers who effectively implement the targeted instructional tasks associated with FMS instruction, (3) identify teachers’ preferred learning methods and support needs for enhancing the quality of physical education classes, and (4) examine the developmental changes observed in students as a result of their participation in the program. In this study, a mixed-method research design was used to answer the research questions. A total of 16 female classroom teachers and 211 students participated from two schools in Ankara. Data were gathered through weekly reflections from teachers, interviews with teachers, PE class observation, and students’ motor competency by using the PLAYbasic tool. Findings revealed that (1) teachers gained knowledge about FMS, PE curriculum literacy, material literacy and they positively improved their attitudes toward teaching FMS, and facilitator played an important role for teachers during the program, (2) teachers followed a consistent PE routine for teaching FMS throughout the program, (3) teachers wanted to improve their teaching strategy at the beginning of the study, they tended to give the role to students in the following weeks in scope of empowered teaching and learning (4) students not only improved their motor competency level but also changed their attitudes toward PE lesson, engagement in activity, improved understanding PE concept. In conclusion, this study adds to the existing body of research by showing how professional development focused on FMS can positively contribute not only teachers’ development but also their students in PE class.Bu çalışmanın amacı uygulama temelli mesleki gelişim programı boyunca (1) sınıf öğretmenlerinin temel motor beceri (TMB) öğretimi ile ilgili deneyimleri araştırmak, (2) TMB öğretimi ile ilişkili hedeflenen görevleri uygulayan öğretmenlerin oranını belirlemek (3) öğretmenlerin beden eğitimi derslerinin kalitesini artırmak için tercih ettikleri öğrenme yöntemlerini ve destek ihtiyaçlarını belirlemek ve (4) programa katılımlarının bir sonucu olarak öğrencilerde gözlemlenen gelişimsel değişiklikleri incelemektir. Bu çalışmada, araştırma sorularını yanıtlamak için karma yöntem araştırma deseni kullanılmıştır. Ankara'daki iki okuldan toplam 16 sınıf öğretmeni ve 211 öğrenci katılmıştır. Veriler, öğretmenlerden alınan haftalık yansıtıcı günlükler, öğretmenlerle yapılan görüşmeler, beden eğitimi dersi gözlemleri ve öğrencilerin motor yeterlilikleri PLAYbasic aracı kullanılarak toplanmıştır. Bulgular, (1) öğretmenlerin temel motor beceri, beden eğitimi müfredat okuryazarlığı, materyal okuryazarlığı hakkında bilgi edindiklerini ve bu becerilerin öğretimine yönelik tutumlarını olumlu yönde geliştirdiklerini, ayrıca kolaylaştırıcının program boyunca öğretmenler için önemli bir rol oynadığını, (2) öğretmenlerin program boyunca temel motor becerileri öğretimi için tutarlı bir beden eğitimi rutini izlediklerini, (3) öğretmenlerin çalışmanın başında öğretim stratejilerini geliştirmek istediklerini, ilerleyen haftalarda güçlendirilmiş öğretme ve öğrenme kapsamında öğrencilere rol verme eğiliminde olduklarını ve (4) öğrencilerin sadece motor yeterlilik düzeylerini geliştirmekle kalmayıp, aynı zamanda beden eğitimi dersine yönelik tutumlarını, aktiviteye katılımlarını ve beden eğitimi kavramlarını anlamalarını geliştirdiklerini ortaya koymuştur. Sonuç olarak, bu çalışma, temel motor beceri odaklı mesleki gelişimin sadece öğretmenlerin gelişimine değil, aynı zamanda beden eğitimi dersinde öğrencilerine de olumlu katkılar sağlayabileceğini göstererek mevcut araştırma literatürüne katkıda bulunmaktadır.Ph.D. - Doctoral ProgramTübita
Challenging homogeneity: Migration-related learner characteristics in refugee-only and mixed-migrant destination language classes in Türkiye and Germany
Get PDFProviding effective destination language education is crucial for the successful transition of newly arrived migrant children into mainstream education. Due to diverse migration patterns, destination language preparatory classes vary in their composition based on the children's migration status. In first-asylum countries, these classes are typically homogeneous, which consist solely of refugee children. In contrast, in resettlement or traditional immigration countries, they tend to be more heterogeneous and accommodate both economic migrants and refugees within the same classroom. This compartmentalized approach, evident in both policy and research, risks limiting the development of transferable, evidence-based insights into destination language education. This multiple case study compares migration-related learner characteristics in homogeneous (refugee-only) and heterogeneous (mixed-migrant) language preparatory classes at the lower-secondary level in Türkiye and Germany. It uses Istanbul and Hamburg as illustrative cases. The study draws on 33 h of classroom observations and 68 semi-structured interviews with key informants, teachers, school administrators, and students. The findings underscore similar multifaceted within-group differences as a defining feature of language preparatory classrooms, regardless of their composition. Migration status alone fails to capture the complexity of newly arrived migrant children. Ethnic diversity is observed not only in mixed-migrant classes in Hamburg but also in refugee-only classes in Istanbul. This challenges assumptions of homogeneity from the same origin country. A second key factor is the presence of newly arrived migrant children with varying schooling trajectories, which further increases within-group differences. Diverse linguistic repertoires characterize both classroom compositions, which are shaped by the dynamic interplay of migration pathways, social background, and prior schooling. These intersecting migration-related characteristics create new forms of stratification and lead to different forms of inequality
METU DBL üzerinde berilyum temelli nötron üretim ışın hattının tasarımı ve simülasyonları
No full textThere are various sources of neutron irradiation for different neutron beam applications, each with their own limitations. Limited access to nuclear reactors, the need to adjust the flux and energy of neutrons, shielding requirements and high costs of laboratory neutron source Cf-252, which has an average neutron kinetic energy of 2.1 MeV that limits its applicability for high energy neutron applications, have led researches to study and adapt accelerator based neutron sources. An ideal source should have an adjustable flux and energy spectrum. One key channel is the 9Be(p, n)9B. By utilizing the METU Defocusing Beam-Line which uses proton cyclotron at TENMAK-NUKEN Proton Accelerator Facility, a beryllium based neutron irradiation station is proposed. This study focuses on design and simulations of a solid target system with optimal parameters such that highest neutron yield with lowest production rate of residual impurity and lowest activity can be achieved during its operation. Using Monte Carlo simulation toolkits such as FLUKA, Geant4, SRIM/TRIM and deterministic nuclear reaction modelling code TALYS, anticipated outcome of the proposed experiment has been extensively studied and are reported here. This thesis reports that by utilizing a 30 MeV, 150 μA proton beam, a beryllium based target setup stationed on METU-DBL can supply neutrons with energy spectrum starting from the epithermal (which can be further decreased to thermal using a moderator), extending to fast and ultra-fast range with a total integrated neutron flux of up to 3x10^10 n/cm2/s at a point on the outer surface of the target station.Farklı nötron ışınlama alanları için birçok nötron kaynağı çözümü bulunmaktadır fakat bu çözümlerin her biri belirli sınırlamaları beraberinde getirir. Nükleer reaktöre ulaşımın sınırlı olduğu, değiştirilebilir nötron akısı ve enerjisi gerekliliği, 2.1 MeV ortalama nötron enerjisine sahip olan ve yüksek enerjili nötron uygulamaları için uygun olmayan Cf-252 laboratuvar kaynağının yüksek maliyeti ve zırhlama gereklilikleri ara¸stırmacıları, hızlandırıcı temelli nötron kaynaklarını araştırıp kullanmaya teşvik etmiştir. İdeal bir nötron kaynağı ayarlanabilir akı ve enerji spektrumuna sahip olmalıdır. Bu temel kanallardan 9Be(p, n)9B öne çıkmaktadır. TENMAK-NÜKEN’de bulunan Proton Hızlandırcı Tesisinde yer alan hızlandırıcı ve onun bir kolu olan ODTÜ Saçılmalı Demet Hattı kullanılarak berilyum temelli bir nötron ışınlama istasyonu önerilmektedir. Bu çalışma, böyle bir katı hedef sisteminin operasyonel haldeyken, optimal parametreler kullanularak en yüksek nötron veriminin elde edilmesine, safsızlık ve ortamda radyoaktiviteye yol açan kalıntı çekirdeklerin en düşük miktarda üretimine odaklanmaktadır. Monte Carlo temelli FLUKA, Geant4, SRIM/TRIM ve deterministik nükleer reaksiyon modelleme kodları TALYS gibi simülasyon kodları kullanılarak önerilen deneyin beklenen çıktıları kapsamlı bir şekilde çalışılmış ve bildirilmiştir. Bu tez, 30 MeV enerjiye sahip 150 μA proton akımı kullanarak METU-DBL’e kurulacak bir berilyum hedef istasyonunun ürettiği nötronların epitermal enerjilerden, hızlı ve ultra-hızlı enerji seviyelerine uzandığını, ve nötron akısının ışınlama istasyonunun yüzeyinde bir noktada 3x10^10 n/cm2/s seviyesine varabileceğini bildirmektedir. Bu tez aynı zamanda nötronların polietilen moderatörden geçirilerek termal enerji seviyelerine indirgenebileceğini öngörmektedir.M.S. - Master of Scienc
Mineralogy and petrology of the late cretaceous rinkite-bearing Başören nepheline-sodalite syenite, Central Türkiye
No full textLate Cretaceous nepheline-sodalite syenites from the Başören area in central-eastern Türkiye include complex Na-K-Ca-Fe-bearing silicates such as rinkite-(Ce) and represents the first occurrence of agpaitic rocks among the extensive Late Cretaceous magmatic units in the region. The Başören nepheline syenites include three distinct rock types: (1) rinkite-bearing early-, (2) rinkite-free late-magmatic rocks, and (3) pyrochlore-bearing, cumulate-like rocks akin to lujavrite found in other layered alkaline igneous complexes such as the Ilímaussaq, South Greenland and the Lovozero, Kola Peninsula, Russia. The Başören rocks exhibit a sodic affinity and demonstrate silica-undersaturated compositions at a minimum pressure of 1 kbar, consistent with their highly fractionated characteristics. The alkalinity indexes [AI = molar [(Na + K) / Al)] and Fe# values [= molar Fe / (Fe + Mg)] of the early- and late-magmatic rocks vary in the ranges of 0.88–1.09, and 0.89–1.00, respectively. The clinopyroxene in these rocks are essentially aegirine augite in composition. However, the cumulate-like lujavritic rocks display higher AI values of 1.16–1.70 and Fe# values of 0.99–1.00 and contain aegirine. Both the early- and late-magmatic samples exhibit several common characteristics, including pronounced depletion in Ba, Sr, Ti, and P, a limited presence or complete absence of high field strength elements relative to the large ion lithophile elements, and considerable variability in the abundances of rare earth elements (REE). The early-magmatic rocks show steep patterns from light REE to medium REE (La to Eu), and convex-upward patterns from medium to heavy REE (Gd to Lu). The late-magmatic samples exhibit similar patterns to the early-magmatic ones but have lower REE abundances. However, the lujavritic rocks display significantly lower REE abundances with convex-downward patterns. Overall, the nepheline-sodalite syenites in the Başören area represent undersaturated melts that were formed by extreme fractionation of silica-undersaturated K-alkaline basaltic magmas generated in a back-arc setting
Modeling and design for metal hydride-based hydrogen storage systems in underwater PEMFC applications
No full textUtilizing metal hydride materials presents a promising avenue for establishing a highly concentrated hydrogen medium suitable for onboard vehicle applications, including underwater contexts. This paper introduces a design solution devised to estimate the characteristics of a metal hydride-based hydrogen storage system tailored for underwater vehicle deployment. The solution facilitates sensitivity analysis across various parameters by offering system mass and volume estimations. The findings highlight the significance of thermodynamic properties and operational conditions in determining the suitability of metal hydrides for compact and efficient hydrogen storage. The study underscores the importance of refueling time, L/D ratio, cooling fluid temperature and velocity, and hydrogen storage capacity in influencing system mass, volume, and thermal management. The model provides insights into the design and optimization of metal hydride-based hydrogen storage systems, offering a comprehensive approach to enhancing performance and reliability for underwater applications
Bankacılık Sektöründe Likidite Yaratımının Belirleyicileri: Türkiye Örneği
No full textThis dissertation examines the key determinants of liquidity creation in the Turkish banking sector, focusing on capital and digitalization. According to financial intermediation theory, banks generate liquidity by serving as intermediaries between borrowers and lenders, collecting deposits and allocating credit. The study employs a dynamic panel data framework, accounting for unobserved common factors. A notable contribution of this research is the application of a two-step instrumental variables approach and principal component analysis to address cross-sectional dependency. It also explores both on-balance sheet and off-balance sheet dimensions of liquidity creation, a largely overlooked area in previous research on the Turkish banking sector. The findings reveal that while higher capital ratios are essential for financial stability, excessive capital can reduce banks' capacity for liquidity creation, particularly when focusing on on-balance sheet positions. This underscores the challenge regulators face in balancing financial stability with the need for liquidity creation to foster economic recovery. Additionally, the study finds that digitalization within banks positively influences on-balance sheet liquidity creation. However, the effect is less significant when considering both on- and off-balance sheet positions, suggesting that digitalization does not affect the amount of transactions in off-balance sheet accounts. Furthermore, the research highlights a negative impact of digitalization across the broader financial system on liquidity creation, emphasizing the need for banks to invest in digital technologies to maintain competitiveness and sustain liquidity creation.Bu tez, Türk bankacılık sektöründeki likidite yaratımının temel belirleyicilerini, özellikle sermaye ve dijitalleşme üzerinde yoğunlaşarak incelemektedir. Finansal aracılık teorisine göre bankalar, mevduat toplayarak ve kredi tahsis ederek borç alanlar ile borç verenler arasında aracılık yaparak likidite yaratırlar. Çalışma, gözlemlenmeyen ortak faktörleri dikkate alarak dinamik bir panel veri çerçevesi kullanmaktadır. Bu çalışmanın önemli bir katkısı, kesitsel bağımlılık sorununu çözmek için iki aşamalı enstrümantal değişkenler yaklaşımı ve temel bileşen analizi kullanılmasıdır. Çalışma ayrıca, Türk bankacılık sektöründe daha önce fazla incelenmeyen hem bilanço içi hem de bilanço dışı işlemler aracılığıyla likidite yaratımını ele almaktadır. Çalışmanın bulgularına göre, yüksek sermaye oranları finansal istikrar için gerekli olsa da aşırı sermaye bankaların likidite yaratma kapasitesini, özellikle bilanço içi işlemlerle likidite yaratımına odaklanıldığında, azaltabilmektedir. Bu durum, düzenleyici otoriteler için finansal istikrar ile ekonomik toparlanmayı destekleyecek şekilde likidite yaratımını teşvik etme ihtiyacı arasında bir denge kurma zorluğunu ortaya koymaktadır. Ayrıca, çalışma, bankalar içindeki dijitalleşmenin bilançodaki likidite yaratımını olumlu yönde etkilediğini ancak hem bilanço içi hem de bilanço dışı işlemler dikkate alındığında bu etkinin önemsiz olduğunu ve dijitalleşmenin bilanço dışı hesaplarda kaydedilen işlemlere miktarsal bir etkisi olmadığını göstermektedir. Buna ek olarak, çalışma tüm finansal sistemde dijitalleşmenin likidite yaratımı üzerinde olumsuz bir etkisi olduğunu ortaya koyarak, bankaların dijital teknolojilere yatırım yaparak rekabetçi kalmalarının ve likidite yaratımını sürdürebilmelerinin önemini vurgulamaktadır.Ph.D. - Doctoral Progra
DDRM-PR: Fourier phase retrieval using denoising diffusion restoration models
Get PDFDiffusion models have demonstrated their utility as learned priors for solving various inverse problems. However, most existing approaches are limited to linear inverse problems. This paper exploits the efficient and unsupervised posterior sampling framework of denoising diffusion restoration models (DDRMs) for the solution of nonlinear phase retrieval problems, which requires reconstructing an image from its noisy intensity-only measurements such as Fourier intensity. The approach combines the model-based alternating-projection methods with the DDRM to utilize pretrained unconditional diffusion priors for phase retrieval. The performance is demonstrated through both simulations and experimental data. The results demonstrate the potential of this approach for improving the alternating-projection methods as well as its limitations