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Article Citation - WoS: 5Citation - Scopus: 5The Design and Techno-Economic Evaluation of Wind Energy Integrated On-Site Hydrogen Fueling Stations for Different Electrolyzer Technologies(Pergamon-Elsevier Science Ltd, 2025) Devrim, Yilser; Ozturk, Reyhan AtabayHydrogen refueling stations (HRS) integrated with renewable energy sources present a pivotal solution for achieving sustainable transportation systems. This study focuses on the design and techno-economic analysis of a grid-connected, on-site hydrogen production HRS powered by wind energy, incorporating various electrolyzer technologies. The selected location for the HRS installation is & Ccedil;anakkale, Turkey, where daily wind speed data has been utilized for performance calculations. The proposed HRS system integrates a wind turbine (WT) with three different electrolyzer technologies: alkaline electrolyzer (AEL), proton exchange membrane electrolyzer (PEMEL), and anion exchange membrane electrolyzer (AEMEL). A comprehensive techno-economic analysis was conducted to evaluate the system's performance, considering factors such as initial capital investment, installation, operation, and replacement costs. The results of the analysis reveal that the levelized cost of hydrogen (LCOH) varies between 9.0 and 18.7 /kg H2, depending on the type of electrolyzer technology used and the daily hydrogen refueling capacity. Notably, increasing the hydrogen refueling capacity significantly reduces production costs. The minimum LCOH of 9.0 /kg H2, achieved under a 20-year investment scenario, corresponds to a refueling capacity of 250 kg H2/day when utilizing the AEL-integrated HRS system. The findings underscore the economic feasibility of on-site hydrogen refueling stations powered by wind energy and utilizing AEL, AEMEL, and PEMEL systems. Among the systems analyzed, the AEL-based HRS system demonstrated the highest return on investment (ROI) of 13.02 % and the shortest payback period (PBP) of 7.7 years, highlighting its economic performance. This study provides valuable insights into the integration of renewable energy with hydrogen production infrastructure, emphasizing the potential of wind-powered HRS systems to advance the sustainability and economic viability of hydrogen-based transportation solutions.Article A Computationally Efficient Approximation for Fractional Differencing: First-Order Operators(Pergamon-Elsevier Science Ltd, 2026) Omay, Tolga; Baleanu, DumitruThis paper introduces the First-Order Fractional Differencing (FOFD) operator that substantially reduces the computational burden of fractional differencing for large-scale applications. While the standard Gr & uuml;nwald-Letnikov (GL) operator requires O(T2) operations for a series of length T, and recent FFT-based methods achieve O(T log T), our FOFD operator requires only O(T) operations through a simple two-point recursion. We develop an optimal weight calibration framework that ensures this computational efficiency does not compromise statistical accuracy, deriving a general formula wopt = d & sdot; (1-0.9 rho)beta(p) that adapts to the persistence structure of autoregressive processes. Empirical applications demonstrate substantial improvements: for the Chicago Fed National Financial Conditions Index with extreme persistence (rho= 0.992), optimal weight calibration reduces approximation error by 93% while preserving the autocorrelation structure of the GL operator. For a series of 10,000 observations, our method requires 20,000 operations compared to 530,000 for FFT-based methods and 50 million for standard implementations-enabling fractional differencing in real-time and high-frequency contexts previously infeasible due to computational constraints. The method's simplicity, requiring no specialized libraries and providing direct implementation through our calibration formula, makes it immediately accessible to practitioners while maintaining the long-memory properties essential for financial time series modeling.Article Legalizing Anti-Gender Ideology and Civil Society Resistance in Turkey(Pergamon-Elsevier Science Ltd, 2026) Keysan, Asuman OzgurThis study investigates how feminist, LGBTQI+, labour, and human rights organisations in Turkey frame and negotiate the legal institutionalisation of anti-gender ideology and how these processes generate strategic yet fragile cross-movement alliances. Drawing on Benford and Snow's framing theory and Yuval-Davis's transversal politics, the analysis is based on semi-structured interviews conducted with activists from ten organisations between April and June 2025 and organisational documents. The study conceptualises anti-gender politics in Turkey not as a societal backlash but as a state-driven, multi-layered project of "masculinist entrenchment (Yetis, & Ozd & uuml;zen, 2024)" that restructures legal, ideological, and affective arenas. The findings demonstrate that activists increasingly reframe anti-gender assaults as systemic attacks on democracy, rights, and equality, producing a shift from issue-based coordination to what this article terms "strategic coexistence", a hybrid alliance formed across previously distant ideological and organisational positions. Diagnostic framing identifies anti-gender reforms as an existential threat, prognostic framing centres on alliance-building, movement memory, and inclusive organisational practices and motivational framing foregrounds shared destiny, solidarity, and the symbolic significance of LGBTQI+ rights. The analysis reveals that while this recontextualisation widens the basis for coalition, the resulting alliance remains structurally unbalanced and fragile. Hierarchical power relations, uneven exposure to political risk, and selective silence, particularly regarding LGBTQI+ concerns, limit the depth and durability of alliances. In this context, LGBTQI+ rights serve both as a catalyst for broad-based mobilisation and as a litmus test for democratic commitment, disclosing the limitations of transversal solidarity under authoritarian regimes.Article Citation - WoS: 1Citation - Scopus: 1International Students' Adaptation in Ankara: The Mediating Roles of Anxiety and Self-Esteem(Pergamon-Elsevier Science Ltd, 2025) AlQaifi, FatenWith globalization, the appeal of studying abroad has grown among university students seeking better educational and career opportunities. However, adapting to a new culture often presents significant challenges, especially as international students face language barriers, cultural differences, and stressors that affect their anxiety, self-esteem, and identity development. Despite the importance of these factors, research on this topic in Turkey remains limited. This study addresses this gap by assessing general anxiety levels of students and examining the relationship between adaptation and identity development among international students, using cross-sectional quantitative methods and self-reported questionnaires. Data from 488 participants were analyzed using SPSS and SmartPLS. Results indicate that both anxiety and self-esteem partially mediate the relationship between identity development and adaptation. Anxiety negatively associates with both identity development and adaptation, while self-esteem shows positive associations with both. Proficiency level and previous travel experience were identified as significant factors influencing students' adaptation. These findings offer valuable insights for universities, policymakers, and other stakeholders in creating a supportive environment that enhances the adaptation experience of international students.Article Citation - WoS: 3Citation - Scopus: 4Intensive Parenting of Mothers in 11 Countries Differing in Individualism, Income Inequality, and Social Mobility(Pergamon-Elsevier Science Ltd, 2025) Lubiewska, Katarzyna; Zeglen, Marta; Lun, Vivian Miu-Chi; Park, Joonha; Runge, Ronja; Muller, Jacomien; van der Kaap-deeder, JoleneAlthough intensive parenting has been found to be mostly detrimental for both children and parents, less is known about the correlates and sources of this type of parenting. This study aimed to examine associations between mother's primary involvement in caregiving and intensive parenting, as well as their potential sources, thereby focusing on: family social status, characteristics of the national economy (income inequality and social mobility) and culture (individualism-collectivism) in 11 culturally diverse countries. Participants were 2535 mothers of children aged between 6 and 10. Mothers reported on their intensive parenting behaviors, entailing both supportive and undermining aspects of meeting their child's needs, as well as their level of involvement in daily caregiving tasks and the subjective family social status. Hypotheses were tested controlling for country level response style. Results revealed that: mothers who were more often the primary caregiver across daily tasks used more intensive parenting behaviors; high social status mothers were using less child need undermining yet more supportive intensive parenting behaviors, and less frequently served as the primary caregiver for daily tasks; the undermining intensive parenting behaviors related positively to country-level individualism and income inequality, whereas relations with social mobility were mixed.Article First-Principles Investigation of Kaolinite/YSZ Heterostructure for Solar-Driven Photocatalytic Hydrogen Production(Pergamon-Elsevier Science Ltd, 2025) Park, Jongee; Yu, Eunmi; Fatima, Syeda AfrinishThis work employs density functional theory (DFT) to elucidate the structural, electronic, and photocatalytic properties of a kaolinite/yttria-stabilized zirconia (Kaol/YSZ) heterostructure tailored for solar-driven hydrogen generation. The lattice mismatch between Kaol(001) and YSZ(111) was determined to be 4.4 % along the a-axis and 2.2 % along the b-axis. Two interface terminations were modeled: an O-terminated Si-O surface and an OH-terminated Al-OH surface. The OH-terminated interface demonstrated a stronger interfacial binding energy (-9.32 eV per cell) and enhanced thermodynamic stability, indicating its suitability for photocatalytic water splitting. Electronic structure analysis reveals that the Kaol/YSZ heterostructure exhibits a narrowed band gap of 1.46 eV relative to the isolated components, which promotes enhanced visible-light absorption. A type-II band alignment is observed, facilitating photoinduced electron transfer from the conduction band of YSZ to the conduction band of Kaol and promoting efficient charge separation. Hirshfeld charge analysis confirms the existence of a built-in electric field at the interface that further drives charge migration. Calculated optical absorption spectra shows a red shift in the heterostructure's absorption edge, extending its photoresponse into the visible region. Under simulated solar irradiation, photogenerated electrons preferentially migrate to Kaol for proton reduction, while holes remain on the YSZ surface to oxidize water, enabling simultaneous H2 evolution and O2 evolution pathways. These findings highlight the promise of the Kaol/YSZ heterostructure as a robust visible-light photocatalyst for sustainable hydrogen production and environmental remediation.Article Performance Assessment of a Solar-Geothermal Based Organic Rankine Cycle System Producing Green Hydrogen(Pergamon-Elsevier Science Ltd, 2026) Atak, Yagmur NalbantThis study presents a comprehensive thermodynamic (energy and exergy) analysis of a solar-geothermal-based Organic Rankine Cycle (ORC) system integrated with a proton exchange membrane (PEM) electrolyzer for green hydrogen production. The system simultaneously harnesses the continuous heat of a geothermal source and the intermittent solar thermal input to ensure stable hydrogen generation. The effects of key operating parameters (solar radiation intensity, production well temperature, inlet temperature of the PTSC fluid, and ORC and PTSC working fluid types were investigated. The results reveal that higher solar radiation intensities significantly enhance both power generation and hydrogen yield, increasing the hydrogen production rate from 22.9 to 24.3 kg/h and the net electrical output from 4.17 to 4.41 MW. Similarly, increasing the geothermal well temperature from 400 K to 600 K significantly enhances hydrogen production, rising from 15.9 to 45.5 kg/h, and increases the net power output by approximately 185 %. However, the exergy efficiency decreases slightly from 0.26 to 0.17 due to increased irreversibilities at higher temperatures. The optimal working pair was determined to be R134a for the ORC and Therminol VP1 for the PTSC, achieving an electrical efficiency of 9.27 %, exergy efficiency of 25.13 %, and hydrogen production rate of 29.02 kg/h. In addition, the exergy analysis showed that the PTSC (similar to 35 %) and condenser (similar to 24.6 %) are the dominant sources of irreversibility. Finally, the Taguchi optimization identified the optimal configuration (Gb = 3.50 x 10(-4) MW/m(2), T-a = 500 K, T-11 = 600 K, and ORC fluid = R134a) yielding the highest overall efficiency and robust performance under variable operating conditions.Article Citation - WoS: 10Citation - Scopus: 10Reliability and Optimal Age-Based Replacement Policy for Consecutive 2-Out System Equipped With Protection Blocks(Pergamon-Elsevier Science Ltd, 2025) Eryilmaz, SerkanThis paper concerns the reliability evaluation and optimal age-based replacement policy for the linear consecutive 2-out-of-n:G system whose two consecutive components are protected by a block that has its own failure rate. Two alternative methods are proposed to compute the reliability of the system. The first method is based on direct probabilistic approach and uses the reliability of the ordinary consecutive 2-outof-n:G system. The second method is based on the concept of survival signature. Closed form equations for the system reliability and the mean number of failed components within the system are obtained. The optimal age-based replacement policy is also defined and studied. Extensive numerical results are presented to illustrate the findings.Article Citation - WoS: 8Citation - Scopus: 6A Review on Membranes for Anion Exchange Membrane Water Electrolyzers(Pergamon-Elsevier Science Ltd, 2026) Altinisik, Hasan; Celebi, Ceren; Ozden, Adnan; Devrim, Yilser; Colpan, C. OzgurAnion exchange membrane water electrolyzers (AEMWEs) - using water and renewable electricity as the input - provide a sustainable pathway to hydrogen production. AEMWEs perform the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) with modest overpotentials at practical current densities (>1 A cm(-2)). The recent catalysis, component, and system-level breakthroughs have enabled significant improvements in current densities and energetic efficiencies. The challenge, however, is to maintain these impressive activities and efficiencies through long-term operation at scale. High-performance, efficient, stable, and economically viable AEMWEs require high-performance, low-cost, and scalable anion exchange membranes (AEMs). This Review provides an overview of physical, chemical, and transport properties of commercial and non-commercial AEMs. The article discusses the operating principles, structures, characteristics, strengths, and weaknesses of conventional and emerging AEMs, along with their performance and stability implications in AEMWEs. The article highlights the characteristics that have intricate implications on performance, stability, and cost. It discusses recent advances and best practices to combine high-performance, efficiency, stability, and low-cost in a single AEM structure. The Review highlights the trade-offs between AEM characteristics, with an overview of emerging approaches that would overcome performance, stability, and cost challenges. The Review concludes by highlighting the research gaps and providing research directions with the potential to take the technology a step closer to wide-scale deployment.Article Potential Localization Strategies and Strategic Instruments in Nuclear Power Generation(Pergamon-Elsevier Science Ltd, 2026) Ege, AhmetDeploying the right strategies is of paramount importance and plays a key role in technology transfer to achieve localization. Today, around 30 countries are considering or embarking on nuclear power programs. What are the potential strategies for nuclear power technology localization? This study attempts to identify localization strategies in nuclear technology and also to unfold tested approaches, business models, strategic legal and technical instruments. The methodology of the study treats the nuclear industry in a state as a "unit" in which a variation of PEST analysis is implemented to reveal macro-environmental factors followed by SWOT analysis to identify strengths, weaknesses, opportunities and threats of available approaches, business models, legal and technical instruments. Four principal strategies emerge: (1) learning by doing; (2) transfer, adopt, assimilate, develop and export; (3) own or operate with limited transfer; and (4) wait and see. The first two strategies are proposed for the countries willing to launch an ambitious nuclear power program. Own or operate with limited transfer strategy can be deployed in those countries prioritizing security of supply, source of reliable base load generation, general economic development, technological and qualified human resources development. Wait and see strategy is convenient for those countries awaiting progress of new technologies or phased out nuclear power but planning to reintroduce it in the future. Regardless of the strategy selected, wise guiding policies and coherent set of actions must be deployed for a successful assimilation and acquisition of the design,
