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Öğe Crowding out or crowding in?: Investment and financialization across generations within family firms in an emerging market(Routledge Journals, Taylor & Francis Ltd, 2025) Doruk, Omer Tugsal; Ergun, BahadirIn this study, we provide new insight into the financialization of the Turkish economy at the intergenerational level for family manufacturing firms from 2001 to 2019, using a dynamic panel generalized method of moments. The results indicate that financialization patterns differ across generations. The second-generation managers achieve a crowding-in effect through non-operational investment income-based financialization, whereas the first-generation managers rely on non-operational interest income channels that crowd out corporate investment. Additionally, professional CEOs use non-operational investment income to reduce real investment, while their use of non-operational interest income supports and increases productive investments within the family-manufacturing firms.Öğe A review of deep learning architectures for plant disease detection(Tubitak Scientific & Technological Research Council Turkey, 2025) Kaya, Yasin; Gursoy, ErcanBackground/aim: The rapid advancement of deep learning (DL) has revolutionized plant disease detection by enabling highly accurate, image-based diagnostic solutions. This review provides a comprehensive synthesis of DL-based methodologies for plant disease detection, systematically structured around the key stages of the modeling pipeline, encompassing data acquisition, preprocessing, augmentation, classification, detection, segmentation, and deployment. Materials and methods: The review focuses on evaluating convolutional neural network (CNN) architectures such as VGG, ResNet, EfficientNet, and DenseNet across diverse experimental contexts. Classification strategies are categorized according to their integration of visualization techniques (e.g., saliency maps, Grad-CAM) to enhance model interpretability, emphasizing the pivotal role of explainable artificial intelligence (XAI) in plant pathology. Object detection models are systematically examined within both one-stage (YOLO, SSD) and two-stage (Faster R-CNN) paradigms. Furthermore, critical challenges-such as environmental variability, data imbalance, and computational constraints-along with potential solutions including transfer learning, synthetic data generation using generative adversarial networks (GANs) and diffusion models, and edge computing for real-time deployment, are comprehensively discussed. Results: This review summarizes best practices for dataset selection and model optimization for mobile platforms, emphasizing their role in improving the efficiency and accuracy of plant disease detection systems. Conclusion: Deep learning-based methods show strong potential to enhance precision and resilience in real-world plant disease detection and monitoring.Öğe Research on Geography's Impact on the 11th-14th Century Cilician Defensive System(Koc Univ Suna & Inan Kıraç Research Center for Mediterranean Civilizations-AKMED, 2025) Kok, Derya SokmenCilicia is a very advantageous region for settlement, as its geography offers security and economic prosperity. The distinctive features of the region have caused Cilicia to host many military struggles throughout history. The defensive structures built at strategic points of the region with the desire for dominance were used by different civilizations for centuries for the same reason. With the addition of new defense structures in the 11th-14th centuries to these existing fortifications, the defense system discussed in this study was formed. Despite having more than one cultural layer, the similarities between them are remarkable. The study focuses on the relationship between the similarities of these defense structures and the geography of Cilicia. For this reason, the regional location, settlement decisions and architecture of 66 defensive structures located on different topographies ranging from sea level to 1500 m altitude were examined in the field in terms of their relationship with the geography of Cilicia. The data obtained are presented in this study under the same thematic headings in a comprehensive manner. Thus, it has been revealed that the Cilician defense system does not only consist of buildings, but that the geography of Cilicia is an integral part of this system.Öğe Deep learning and explainable AI for email phishing classification: A comparative study of TabNet, NODE and FT-transformer models(Gazi Univ, 2025) Asal, Burcak; Oyucu, Saadin; Dogan, Ferdi; Polat, Onur; Aksoz, AhmetIn the changing landscape of cybersecurity threats, phishing emails indicate a persistent and damaging attack vector. This study investigates the effectiveness of deep learning models on a phishing email classification task using tabular data and focusing on TabNet, NODE (Neural Oblivious Decision Ensembles), and FT-Transformer architectures. The utilized dataset includes eight input features capturing linguistic and structural characteristics of emails, with a binary label indicating phishing or normal classification. Additionally, the NearMiss under-sampling approach is applied to address the significant class imbalance. Experimental results demonstrate that while all three models achieve strong performance, the FT-Transformer model outperforms TabNet and NODE by achieving the highest classification accuracy and balanced precision-recall scores. Additionally, explainable artificial intelligence (XAI) methods, SHAP and LIME, are employed to interpret the FT-Transformer model's decision-making process, which highlights the critical role of spelling errors, unique word counts, and urgency-related keywords in phishing detection. The findings emphasize the potential of transformer-based approaches for tabular cybersecurity applications and indicate the importance of interpretable AI in enhancing trust and transparency in phishing detection systems.Öğe Portfolio Optimisation in the Cryptocurrency Market: Hybrid Integration of Markowitz and Ridge Methods(İstanbul Univ, 2025) Yildirim, Ruya Kaplan; Munyas, Turgay; Aydin, Gulden KadoogluConstructing an effective asset allocation strategy requires buildingwell-diversified portfolios that maintain robust performance beyond the sample data. The classical Markowitz portfolio optimisation, while widely used, is known to suffer from issues such as estimation errors and sensitivity to multicollinearity, which can significantly distort the allocation process and reduce performance reliability. In order to surmount the aforementioned challenges, the incorporation of Machine Learning echniques, specifically Ridge regression, into the portfolio creation process has been effected. This has resulted in the provision of a hybrid model that combines the strengths of Markowitz optimisation and Ridge regression. The integration of these approaches within the hybrid model serves to mitigate the prediction risks while maintaining the diversification benefits inherent to the Markowitz framework. The model was trained using an 80/20 split and cross-validation was employed to prevent overfitting. The findings indicate that this integrated approach attains the maximum Sharpe ratio, thereby significantly enhancing risk-adjusted returns and portfolio stability when applied to cryptoasset returns. The findings emphasise the merits of integrating classical optimisation methodologies with machine learning to develop more robust and adaptive asset allocation strategies. By analysing the impact of high-volatility cryptoassets on portfolio performance, it makes important contributions to both the literature and practical portfolio strategies for investors.Öğe Exergy Calculations and Refrigerant Selection Using Flue Gas Waste Heat in Organic Rankine Cycle(Gazi Univ, 2025) Saru, Muhsine; Sozen, Adnan; Pulat, ErhanIn this study, the second law efficiency of the organic Rankine cycle (ORC) designed was calculated for each of refrigerants, and the exergies of the ORC components were examined separately. Candidate refrigerants were determined for comparison. When determining candidate refrigerants, the first thing to consider was the low boiling point temperature. Five candidate refrigerants were determined for comparison purposes, namely R290, R600a, R32, R125, R143a. When determining candidate refrigerants, importance was given to the criterion that their boiling temperature should be lower than the boiling temperature of water. The refrigerant with the highest exergy efficiency was selected as the most suitable refrigerant among the candidate refrigerants. The temperature of sink has been taken as a value that lower than the boiling point temperature o the refrigerant that has the lowest boiling point temperature among the others instead of ambient temperature.The power generation, first law efficiency and second law efficiency of R32were found to be 170,3 kJ/kg, 0,3049 and 0,284, respectively.The thermal efficiency and second law efficiency values of the ORC using R32 are higher than those using other refrigerants for conditions in the considered textile plant.Öğe Ekonomi Politika Belirsizliğinin ve Para Politikası Belirsizliğinin Kripto Para Piyasası Üzerindeki Etkisi(Sosyoekonomi Society, 2025) Kadooglu-Aydin, Gulden; Kaplan-Yildirim, Ruya; Munyas, TurgayThis study examines how Economic Policy Uncertainty (EPU) and Monetary Policy Uncertainty (MPU) affect the returns often different cryptoassets using Quantile Regression (QR) and Robust Least Squares (RLS) methods. Quantile regression allows a nuanced examination of how these uncertainties affect returns at different levels under market conditions. Using monthly data from January 1, 2018, to June 1, 2024, the analysis shows that MPU has a negative impact on cryptoasset returns under normal and bull market conditions. However, this effect diminishes during bear market periods. Conversely, EPU has a significant negative impact only during bull markets. These results suggest that market conditions critically shape the sensitivity of cryptoassets to uncertainty, with such effects amplified during bull market periods.Öğe Assessment of phenolic composition, sugars, and antioxidant capacity in Turkish fig (Ficus carica L.) cultivars(Tubitak Scientific & Technological Research Council Turkey, 2025) Zahid, Ghassan; Kelebek, Hasim; Kuden, Ayzin; Shimira, Flavien; Kacar, Yildiz AkaFig fruits (Ficus carica L.) have significant health benefits. T & uuml;rkiye is the leading fig producer in the world. Despite their diversity and rich medicinal properties, the biochemical fingerprints and nutritional quality of local figs are poorly understood. This study aimed to analyze the peels and pulps of eight Turkish figs with varying colors for their total phenolic composition, sugars, and antioxidant capacity. Thirty-one phenolic compounds (PCs) were detected using HPLC-MS/MS. The dark-purple 01-1N-58 genotype had the highest amount of colored PCs in fruit peels and pulps (151.25 and 31.57 mg/100 g dw, respectively). Likewise, the maximum quantity of colorless PCs was found in the peels of the same genotype (1063.91 mg GAE/100 g dw). The highest antioxidant capacity was also observed in the 01-1N-58 genotype. Cyanidin-3-O-rutinoside and chlorogenic acid were the dominant PCs in the peels and pulps. This study showed that the fig fruit peels, especially with darker colors, had a greater total quantity of bioactive compounds than pulp. High variability was observed among the studied cultivars and genotypes, which is crucial to help fig breeding researchers, consumers, and the food industry to select fig varieties with the most health benefits.Öğe Generalized Hukuhara diamond-alpha derivative of fuzzy valued functions on time scales(Ankara University Faculty of Sciences, 2025) Bayeg, Selami; Mert, Funda RaziyeIn the literature, the delta and nabla derivatives have been considered separately in the study of fuzzy number valued functions on time scales. In this paper, to unify these two derivatives for fuzzy number valued functions, we propose a new dynamic derivative called the diamond-alpha derivative, defined via the generalized Hukuhara difference. We establish several fundamental properties of the diamond-alpha derivative and investigate a particular class of fuzzy initial value problems on time scales with respect to this new derivative. Additionally, we provide numerical examples to illustrate our results.Öğe The Relationship between Language and the Self: The Effects of Aphasia on the Self(İstanbul Univ, Fac Letters, Dept Psychology, 2025) Cifteci, Volkan; Cifteci, Nevin YilmazIt is traditionally considered that there is a correspondence between language and the mind. That is, languageis taken to be a mirror of the mind. Another view claims that language is the mind's most essential component.It is difficult to separate language, so closely linked with the mind, from the concept of self. This study aims toclarify the relationship between language and the self. The human self and language are constructed through atemporal process. Therefore, the concepts of self and language need to be evaluated developmentally. The purposeof this study is to shed light on the relationship between language and self through aphasia. This relationship ispresented by emphasizing the key role language plays in a person's understanding of the world, themselves, andothers. The world, in which people name objects and represent events through language, is defined both as a realmof existence in which humans reside and as a network of relationships that allows connection with others. Languageis considered a comprehensive subject that encompasses syntax, semantics, and pragmatics. The self is viewed asa concept that can be understood within the framework of consciousness, self-consciousness, and social relation.The study demonstrates a parallel between the three components of language and those of the self. By examiningthe effects of aphasia on syntax, semantics, and pragmatics, the study demonstrates how this disorder negatively impacts a person's awareness of the world, their own self, and their relationships with others. This study attemptedto answer crucial questions such as the role of language in experiencing the world, understanding oneself, andrelating to others, as well as how the loss of language in aphasia affects the self.Öğe Examining the Security Dimension of the Organization of Turkic States by Addressing Border Issues: Kyrgyz-Tajik Border Conflict(Ahmet Yesevi Univ, 2025) Erendor, Mehmet Emin; Citak, EmreThis study aims to evaluate the Organization of Turkic States' approach to security with a special focus on border issues in the region after the collapse of the Soviet Union. The emergence of independent states in the Caucasus and Central Asia led to border conflicts with neighbouring countries. While some of these disputes have been resolved through agreements, others persist. Given the potential for border issues to escalate into conflicts, achieving peaceful resolutions is crucial for regional stability and fostering interstate cooperation. Within this framework, 1999 Batken Events hold significant importance. These events not only epitomize the persistent border issues between Kyrgyzstan and Tajikistan but also bring regional border disputes into the forefront of attention. Today, border disputes present a significant challenge for the Organization of Turkic States, which is expanding its cooperation among member states and claims to pursue an effective security strategy. It can be argued that the OTS's efficiency in peacefully resolving border disputes, which are sensitive security matters, could directly affect the organization's future international standing.Öğe Financial Profile of Zombie Firms: Evidence from the Emerging Turkish Market(Sosyoekonomi Society, 2025) Sahin, ArzuThis study examines the financial profile of zombie companies that damage other firms, sectors, and the economy in T & uuml;rkiye, an emerging market. To investigate the factors affecting the likelihood of becoming a zombie company, panel probit models are estimated using 241 non-financial listed firms on Borsa Istanbul from 2013 to 2019. Among these firms, 64 are classified as zombies. The results indicate that the probability of becoming a zombie is higher in companies that are more indebted, less efficient in asset usage, and younger. That is, less experienced companies that invest heavily in inefficient assets have the potential to become zombies and harm the economy in the long run.Öğe DOES GEOPOLITICAL RISK RISE CARBON EMISSIONS? EVIDENCE FROM ACS-ARDL MODEL FOR OECD COUNTRIES(Economic and Financial Research Assoc - EFAD, 2025) Can, Zeynep GizemGeopolitical risk constitutes an escalating global challenge, exerting profound implications for carbon emissions and the stability of ecological systems. This paper investigates the nexus between geopolitical risk and carbon emissions by employing advanced econometric techniques on a balanced panel of 25 OECD member states, incorporating extensive pre-estimation diagnostics and robustness checks to ensure methodological rigor. The empirical evidence demonstrates that elevated geopolitical risk exerts a statistically significant and positive effect on carbon emissions, thereby intensifying environmental degradation. Moreover, population expansion and higher per capita GDP are identified as key drivers of ecological deterioration, while trade openness and financial development emerge as mitigating factors. These results underscore the critical importance of fostering cross-border dialogue and enhancing institutional platforms established by supranational bodies to reduce geopolitical tensions. Coordinated international strategies that address both political stability and environmental sustainability are thus imperative for mitigating the intertwined challenges of global security and climate change.Öğe Financing Challenges of the Agriculture: A Comprehensive Sectoral and Company-Level Financial Analysis for Türkiye(Eskisehir Osmangazi Univ, Fac Education, 2025) Sahin, ArzuIn this study, a financial analysis was conducted on the agricultural sector of T & uuml;rkiye-which has a disproportionately low share in the real sector and stock market relative to its added value-as well as on a selected listed company within the sector for the period 2016-2022. The findings indicate that the sector's reliance on short-term borrowing to meet its external financing needs arising from low asset turnover and profitability increases financial risk and weakens both liquidity and profitability. The company chosen for the analysis managed to reduce borrowing costs and improve profitability through a strong financial structure and agricultural incentives. Despite structural and financial challenges, the sector offers growth and profit opportunities for companies with robust financial foundations.Öğe Sectoral Concentration in Loans and Credit Risk: An Examination by Company Accounts in Turkey(Mehmet Akif Ersoy Univ, 2024) Sahin, Arzu; Acar, ElifThis study examines the impact of sectoral concentration on credit default risk, drawing from economic theory and portfolio management principles, utilizing the Turkish aggregated sector-level data and banking data from 2009 to 2022. The study employs a panel data analysis framework to investigate the relationship between sectoral diversification in loans and credit risk, controlling for sector-specific variables. Unlike previous studies primarily reliant on banking system data, this research broadens the scope by incorporating the real sector credit usage data for the measurement of concentration. Additionally, instead of the commonly used Herfindahl-Hirschman Index, the study employs the Sector Concentration Index as a measure of concentration, allowing for a comparison of sector distribution with an ideal market sector distribution. The analysis considers not only the widely used indicator of credit risk, non-performing loans ratio in the banking system but also bad debt ratios in the real sector, thereby enhancing the understanding of credit risk dynamics. The analysis results, which show a significant positive relationship between sectoral concentration indices and non-performing ratios employed, reveal that sectoral credit concentration has an increasing effect on the credit risk level and offers insights into the optimal diversification strategies for mitigating credit risk in the banking sector.Öğe Exploring the Ecological Footprint in Turkey: Analyzing the Interplay of Economic and Environmental Factors(ESKİŞEHİR OSMANGAZİ ÜNİVERSİTESİ, 2024) Demirbay, Sevim Gülin; Karakaş, EsraNowadays, 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.Öğe Need to Belong and Cognitive Flexibility in Young Adults: Mediating Role of Negative Affect and Moderating Role of Agreeableness(Current Approaches in Psychiatry, 2024) Yılmaz, Selin ; Alan, RanaObjective: Previous studies propose that the need to belong can explain some emotional and cognitive mechanisms. Yet, it is unclear which cognitive and emotional mechanisms may be predicted by the need to belong and whether this relationship varies within different personality traits. The general purpose of this study was to scrutinize the role of emotion and personal traits in the relationship between the need to belong and cognitive flexibility with the help of a model. Method: A total of 719 university students, 446 female and 273 male, employed the participant group of the study (M ± SDage = 21.38 ± 1.97). Data measurement tools were Standard Information Form, Cognitive Flexibility Scale, Need to Belong Scale, Big Five Personality Traits Scale, Positive and Negative Affect Scale. Results: The mediation analysis demonstrated a significant indirect effect of the need to belong on cognitive flexibility through negative affect (b =-.0606, t = -3.189). This finding showed that the need to belong reduced cognitive flexibility by increasing negative affect. With regard to the moderation analysis results, the interaction effect of the need to belong and agreeableness personality trait (need to belong X agreeableness) significantly predicted cognitive flexibility (b =-.1169; CI 95% =-.2033 to -.0304, t =-2.6542, p = 0.0081). Accordingly, the negative direct effect of the need to belong on cognitive flexibility was stronger in the lower agreeableness condition. Conclusion: The current study indicated that agreeableness moderates the negative effect of the need to belong on cognitive flexibility. The highest cognitive flexibility was observed in the lower need to belong and higher agreeableness conditions. In conclusion, it is suggested that the effect of the need to belong on cognitive abilities may be accompanied by personality traits and emotional processes.Öğe Comparative Performance Analysis of PMSGs Using Various Core Materials for Wind Turbine Application(Osmaniye Korkut Ata University The Institute of Science and Technology, 2024) Esenboğa, BurakPermanent Magnet Synchronous Generator (PMSG) cores play an important role in determining the performance of wind power. Core materials of PMSGs influence magnetic flux density, minimize losses, facilitate heat dissipation, ensure mechanical stability, and balance cost considerations. The use of different core materials has a significant impact on PMSG systems efficiency and overall performance in wind generation. Therefore, this study provides a comparative performance analysis for PMSG systems using diverse core materials in wind turbine applications. The design and analysis methodology is based on ANSYS/MAXWELL simulation software. The proposed model for a wind turbine is designed with 380 V, 50 Hz, and 24 HP output power. The study investigates the performance characteristics of PMSG systems utilizing various core materials such as silicon steel, amorphous steel, and ferrite materials. During the design phase, the Finite Element Analysis (FEA) is performed to compare core materials using ANSYS Maxwell. The results demonstrate the effectiveness and accuracy of the design approach using different core materials. The results help guide the selection of the best core materials to improve the efficiency and sustainability of wind energy systems based on PMSG.Öğe INVESTIGATION OF THE VARIOUS TAPER ANGLE OF THE TIP AND ANGLE OF THE CONICAL SHAPE OF AN AEROSPIKE NOZZLE(Konya Teknik University , 2024) Bayir, Şerif Bilalhan ; Akbıyık, HürremThis study considers the design of aerospike nozzles and the thrust measurement experiments conducted with various designs, taking into account existing research in the literature. Unlike other studies, this experimental study examines the effects of the angle of the conical shape and the taper angle at the tip of the aerospike nozzle on thrust. Thrust measurement experiments were conducted using a cold gas system. All measurement results were compared, revealing that the design parameters for aerospike nozzle efficiency in this study were a conical shape angle of 45° following the main flow passage and a tapering angle of 30° at the tip of the aerospike nozzle. Additionally, it appears that the taper angle and conical angle of the aerospike nozzle are interrelated in thrust production.Öğe DETERMINING TURKISH HOUSEHOLDS' TOURISM CONSUMPTION EXPENDITURES IN ECONOMIC CRISIS(Akdeniz Univ Tourism Fac, 2019) Gul, HasanCrises may influence the most economies differently in the world and cause to diminish their national wealth and rise in unemployment rates. As a developing country, Turkey has been impressed by some economic slumps in the world in different periods. This study aims to investigate the tourism participation of households and estimate the most sensitive household groups after the 2008 financial crisis by employing Heckman two-stage model. It also reveals which household groups change their tourism consumption expenditures more in Turkey. The results show that variations in income elasticity during the crisis are different to household groups. In other words, households with high income level were not significantly affected by the world economic crisis, while households with low income reduced tourism consumption expenditures both in domestic and outbound tourism.
