Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Fine-Tuning Large Language Models for Turkish Flutter Code Generation(Sakarya University, 2025-12-29) Uluırmak, Buğra Alperen; Kurban, RifatThe rapid advancement of large language models (LLMs) for code generation has largely centered on English programming queries. This paper focuses on a low-resource language scenario, specifically Turkish, in the context of Flutter mobile app development. Two representative LLMs (a 4B-parameter multilingual model and a 3B code-specialized model) on a new Turkish question-and-answer dataset for Flutter/Dart are fine-tuned in this study. Fine-tuning with parameter-efficient techniques yields dramatic improvements in code generation quality: Bilingual Evaluation Understudy (BLEU), Recall-Oriented Understudy for Gisting Evaluation (ROUGE-L), Metric for Evaluation of Translation with Explicit Ordering (METEOR), Bidirectional Encoder Representations from Transformers Score (BERTScore), and CodeBLEU scores show significant increases. The rate of correct solutions increased from ~30–70% (for base models) to 80–90% after fine-tuning. The performance trade-offs between models are analyzed, revealing that the multilingual model slightly outperforms the code-focused model in accuracy after fine-tuning. However, the code-focused model demonstrates faster inference speeds. These results demonstrate that even with very limited non-English training data, customizing LLMs can bridge the gap in code generation, enabling high-quality assistance for Turkish developers comparable to that for English. The dataset was released on GitHub to facilitate further research in multilingual code generation.Article Comparative Assessment of Smooth and Non-Smooth Optimization Solvers in HANSO Software(Balikesir University, 2021-10-27) Tor, Ali HakanThe aim of this study is to compare the performance of smooth and nonsmooth mization) software. The smooth optimization solver is the implementation of the Broyden-Fletcher-Goldfarb-Shanno (BFGS) method and the nonsmooth optimization solver is the Hybrid Algorithm for Nonsmooth Optimization. More precisely, the nonsmooth optimization algorithm is the combination of the BFGS and the Gradient Sampling Algorithm (GSA). We use well-known collection of academic test problems for nonsmooth optimization containing both convex and nonconvex problems. The motivation for this research is the importance of the comparative assessment of smooth optimization methods for solving nonsmooth optimization problems. This assessment will demonstrate how successful is the BFGS method for solving nonsmooth optimization problems in comparison with the nonsmooth optimization solver from HANSO. Performance profiles using the number iterations, the number of function evaluations and the number of subgradient evaluations are used to compare solvers.Article Deprem Anında ve Sonrasında Dönüşebilen Tasarım Önerileri: Günlük Kullanımdan Hayat Kurtaran Birimlere(Afet ve Acil Durum Yonetimi Baskanligi (AFAD), 2025-12-30) Özmen, Nihan Muş; Kurtuluş, Vacide BetülDepremler, yıkılan binalar ve devrilen eşyalar nedeniyle meydana gelen yaralanmalarla insan hayatını ciddi şekilde tehdit etmektedir. Bu çalışma, mobilyalara kendini kurtarma alanları entegre ederek ezilme yaralanmalarını önlemeyi ve deprem sonrası barınma ihtiyaçlarını karşılamayı amaçlayan tasarım önerileri sunmaktır. 2022 Güz döneminde Abdullah Gül Üniversitesi Deneysel Tasarım Stüdyosu kapsamında yürütülen çalışma, tanınmış bir mobilya tasarım firmasıyla iş birliği içinde gerçekleştirilmiştir. Öğrenciler hem günlük yaşamda işlevsel hem de afet anlarında acil barınma alanı olarak kullanılabilecek çift amaçlı mobilya tasarımları geliştirmiştir. Projeler, deprem sırasında ve sonrasında kullanılmak üzere iki ana kategoriye ayrılmış; yaşam ve çalışma mekânlarında, dönüşebilir mobilya tasarımlarına odaklanmıştır. Bulgular, işlevsel ve uyarlanabilir tasarımlar yoluyla risk azaltma ve deprem sonrası uyum konularında yenilikçi yaklaşımları ortaya koymaktadır.Article Noninvasive Condition Monitoring for Eccentricity Fault Detection in Large Hydro Generators(TÜBİTAK Scientific & Technological Research Council Turkey, 2026-01-16) Lemeski, Atena Tazikeh; Tekgun, Didem; Keysan, Ozan; Leblebicioglu, Kemal; Gol, Murat; Leblebicioglu, Mehmet KemalEccentricity faults in electric machines remain a critical concern, as they generate uneven magnetic forces that increase vibration and noise, ultimately raising the risk of premature motor failure. This study proposes a method for the early detection of dynamic eccentricity (DE) faults in hydropower plants through an advanced optimization-based parameter identification technique integrated with finite element analysis (FEA). Finite element modeling (FEM) is first used to analyze an existing salient-pole synchronous generator (SPSG) from a hydroelectric power plant in T & uuml;rkiye. The effects of DE faults on the SPSG's magnetic equivalent circuit parameters are then examined under various fault severities. A comprehensive hydropower plant model-including the synchronous generator, governor, and excitation system-is developed in MATLAB/Simulink, with all input parameters obtained from real plant data and equivalent circuit variations extracted from FEA. After completing the modeling stage, including fault scenarios, MATLAB and Simulink are employed together to estimate key magnetic equivalent circuit parameters using a modified particle swarm optimization (MPSO) algorithm, achieving highly accurate parameter estimation. Since the hydropower system allows measurement of the three-phase output currents, parameter estimation is performed based on current variations under different fault conditions. The simulation results verify the method's ability to detect faults with high accuracy; thus, this integrated and noninvasive approach provides a robust framework for ensuring the operational reliability and longevity of large hydro generators.Article Spatial Dimension of the Local Phenomenon in Kayseri(Gazi University, Faculty of Engineering Architecture, 2025-12-31) Ozmen, Nihan Mus; Asiliskender, BurakKayseri is in the centre of Anatolia, at the intersection of trade and military routes, and possesses a rich cultural heritage. Throughout its history, the city has hosted various civilizations, developing around a central castle and continuing to expand, particularly after the 19th century. Kayseri has long served as a meeting point for diverse cultures. Within this diversity, families known as locals, whose origins date back to the oldest neighbourhoods within the city walls, have held significant mercantile power. These local families regard themselves as the actual owners of Kayseri and have influenced the city's developmental trajectory. Over time, they have moved outward from the centre to newly developed neighbourhoods, first to the north and then to the east. This study examines the urban development of Kayseri in the 20th century and the spatial mobility of these local families. It employs qualitative methods such as ethnographic observation, oral history interviews, and GIS-based thematic mapping to analyse these movements in a multi-layered way. The study also aims to understand Kayseri's socio-cultural dynamics and historical texture by investigating the role of local families in the city's physical and functional transformations. In this context, it addresses the physical and functional changes in neighbourhoods vacated by these relocations.Article Citation - Scopus: 1Kayseri İlindeki Bazı Tarihi Eserlerde Bozunma Etkilerinin Tahribatsız Deney Yöntemleriyle Değerlendirilmesi(TMMOB Chamber of Geological Engineers, 2025-06-11) Akin, Mutluhan; Akin, Muge; Akgül, Muhammed Kamilİç Anadolu’da önemli bir yerleşim merkezi olan Kayseri, farklı dönemlerden günümüze kadar gelen birçok tarihi esere ev sahipliği yapmaktadır. İlin farklı bölgelerinde özellikle yoğun yerleşimin bulunduğu alanlarda, Selçuklu Dönemi’ne ait 12. ve 14. yüzyıllar arası yapılmış çok sayıda cami, kümbet ve medrese türü tarihi esere rastlamak mümkündür. Kültürel miras niteliğindeki bu eserler çoğunlukla yakın çevrede yoğun olarak bulunan farklı renk ve dokudaki ignimbirit türü kaya malzemesi kullanılarak inşa edilmişlerdir. Genel olarak düşük dayanıma sahip ve su etkilerine karşı hassas olan bu ignimbiritler zaman içerisinde atmosferik etkenler, hava kirliği, vandalizm vb. gibi olaylar sonucunda bozunmakta ve ilksel özelliklerini kaybetmektedirler. Bu çalışmada Kayseri il merkezindeki Roma ve Selçuklu dönemlerine ait tarihi eserler ile bu eserlerde zaman içinde meydana gelen bozunma etkileri incelenmiştir. Bozunma etkilerinin gözlemsel olarak incelenmesinin yanı sıra, eserlere herhangi bir zararı bulunmayan tahribatsız deney yöntemlerinden İğne Penetrometresi, Schmidt Çekici ve P-dalga hızı deneylerinden faydalanılmıştır. Bunun yanı sıra, bozunmuş ignimbirit bloklarına ait yerinde deneylerle belirlenen değerler, aynı malzemeye ait taze örneklerin fiziko-mekanik özellikleri ile karşılaştırılmıştır. Yapılan değerlendirmeler sonucunda tarihi eserlerin taban bölümlerinde özellikle kılcallık sebebiyle pullanma ve kavlaklanma türü bozunmaların geliştiği ve ignimbiritlerin bu bölümlerde dayanımlarını önemli ölçüde kaybettiği tespit edilmiştir. İncelenen kümbetlerin bazılarına uygulanan iyileştirme çalışmalarında ise kümbetlerin çevresinde bulunan yüzey suyu drenajlarının yeterli ölçüde yapılamadığı ve yağmur ile biriken suların tarihi eserlerin daha fazla bozunmasına sebep olduğu saptanmıştır. Kültürel miras olarak değerlendirilen bu tarihi yapıların korunup gelecek nesillere aktarılması amacıyla, ignimbirit yapılarının yüzeysularına karşı duyarlılığı dikkate alınarak tarihi kümbetlerin çevresinde su drenajı iyileştirme çalışmaları yapılması önerilmektedir.Article Citation - Scopus: 2Zeolite Synthesis by Alkali Fusion Method Using Two Different Fly Ashes Derived From Turkish Thermal Power Plants(Chamber of Mining Engineers of Turkey, 2020-03-01) Top, S.; Vapur, HüseyinIn this study, Faujasite (Na-LSX) (3.5(Ca0.3)3.5(Na0.6)3.5(Mg0.1)Al7Si17O48 32(H2O)) type zeolites and Ca-Filipsite (CaK0.6Na0.4Si5.2Al2.8O16 6(H2O)) type zeolites were produced from Sugözü Thermal Power Plant and Çatalaǧzi Thermal Power Plant fly ashes by alkali fusion method followed by water leaching, respectively. In these methods, fly ashes and sodium hydroxide (NaOH) were mixed in certain proportions and sintered at 600°C in ash furnace. Then, zeolites were obtained from the ground materials after water leaching and solid/liquid separation, respectively. Cation Exchange Capacity (CEC), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), X-Ray Fluorescence (XRF) and Atomic Absorption Spectrometer (AAS) analyses were used to characterize the synthesized zeolites. The zeolites synthesized with Sugözü fly ashes in a ratio of 1:2 had 136.93 meq/100 g CEC, whereas the CEC of synthesized zeolite from Çatalaǧzi fly ashes was found to be 247.88 meq/100 g. As a result, zeolites, which can be used as wastewater treatment agent, energy storage material, catalyst and separator, were synthesized by using 2 different Class F fly ash. © 2023 Elsevier B.V., All rights reserved.Article Thermal Stresses in SOFC Stacks: The Role of Mismatch Among Thermal Conductivity of Adjacent Components(Tubitak Scientific & Technological Research Council Turkey, 2021-06-30) Aydin, Ozgur; Matsumoto, Go; Shiratori, YusukeGenerating power from renewable biogas in solid oxide fuel cells (SOFCs) is an environment-friendly, efficient, and promising energy conversion process. Biogas can be used in SOFCs via a reforming process for which dry reforming is more suitable as the reforming agent exists in the biogas mixture. Biogas can be directly reformed to H-2 -rich fuel stream in the anode chamber of a SOFC by the heat released during power generation. Exploiting the heat and water produced in the SOFC for internal reforming of biogas makes the energy conversion process very efficient; however, various challenges are reported. Thus, indirect internal reforming is opted for which a separate reforming domain is required. In an indirect internal reformer operating at usual conditions, dry reforming rate is quite high in the inlet and it decreases steeply toward the fuel outlet. Great temperature gradients develop over the reformer, since the dry reforming reaction is strongly endothermic. The abruptly varying rate of the reforming reaction affects the temperature fields in the adjacent components of SOFC and hence intolerable thermal stresses emerge on the SOFC components. In our preceding study, we graded the reforming domain, homogenized the temperature profile over the reforming domain, and executed performance and durability experiments. However, most of the experiments failed due to fracturing SOFC components hinting at existence of thermal stresses. In that study, we focused on minimizing the temperature gradients within the reforming domain; namely, we neglected the other processes. To eliminate the thermal stresses, we modeled the entire module of SOFC equipped with a reformer featuring a graded reforming domain. We found that the mismatch between the thermal conductivities of the adjacent module components is the major reason for the thermal stresses. When the mismatch is eliminated, thermal stresses disappear even if the reforming domain is not graded.Article Theoretical Investigation of Steric Effects on the S1 Potential Energy Surface of O-Carborane Derivatives(Tubitak Scientific & Technological Research Council Turkey, 2023-01-01) Alkan, FahriTDDFT scan calculations were performed for s-carborane-anthracene derivatives (o-CB-X-Ant where X=-H,-CH3,-C2H5 and tert-butyl or-tBu) in order to understand the interplay between the steric effects, S1 potential energy surface (PES) and photophysical properties. The results show that all systems exhibit three local minima on the S1 PES, which correspond to the emissive LE and TICT state, along with the nonemissive CT state respectively. In the case of the unsubstituted system (o-CB-H-Ant), and-CH3 and-C2H5 substituted cases, S1 PES is predicted to be quite flat for certain conformations indicating that it is possible for these systems to reach the nonemissive CT state without a large energy penalty. In comparison, conformational pathways for the nonemissive CT state are predicted to be energetically unfavorable for o-CB-tBu-Ant as a result of both steric and electronic effects. These results provide a mechanism for the enhanced emission of cr-CB-fluorophore molecules with bulky ligands.Article Citation - WoS: 2Citation - Scopus: 2The Nexus of Leadership, Political Empowerment, and Social Mobilization: The Case of the July 15 Coup Attempt in Turkey(Seta Foundation, 2020-06-30) Donmez, Rasim Ozgur; Timur, Kasim; Lloyd, Fatma Armagan TekeThis study analyzes the mutually empowering relations between Turkish President Recep Tayyip Erdogan and his followers, and how Erdogan's charismatic leadership and image functioned to galvanize his followers on the night of July 15, 2016, when large numbers of them mobilized against the attempted coup. The article has three sections. The first is a theoretical discussion which sheds light on the concept and the underlying mechanisms of political empowerment and its effects on the relationships between leaders and followers. The second section evaluates Erdogan's characteristics and ruling style, which was instrumental in motivating resistance to the abortive coup. Finally, the third section analyzes the various means by which Erdogan was able to inspire the masses to mobilize against the armed junta through interviews and observations.