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Öğe Financial Management of Traditional and Complementary Medicine in Türkiye Public Hospitals: A Policy Analysis of Pricing, Accounting, and Performance Incentives(Wiley, 2026) Kilinc, MehmetThis article presents a policy analysis of the financial management of Traditional and Complementary Medicine (T&CM) practices in public hospitals in T & uuml;rkiye, with a focus on the intersection of pricing, accounting, and performance-based supplementary payment systems. While integrating T&CM into the modern healthcare system expands treatment options, it introduces significant administrative challenges. In recent years, the presentation of T&CM applications in public hospitals in T & uuml;rkiye has become widespread. However, this expansion has raised critical questions, such as how these services will be charged and how the revenue generated will be accounted for. In this context, the extent to which current pricing policies support the sustainability of T&CM services is discussed. Adopting a descriptive policy analysis approach supported by analytical simulations, this study assesses the adequacy of current pricing policies. The findings reveal a systemic "performance paradox": although time-intensive, T&CM procedures yield significantly lower performance scores per hour than standard outpatient services, creating a structural disincentive for physicians. Furthermore, the lack of transparency in cost-center accounting complicates the financial sustainability of these units. The study concludes by offering tiered policy recommendations-ranging from low-effort coefficient adjustments to high-effort payment model reforms-to align financial incentives with the strategic goal of integrating T&CM into the public health system.Öğe Hot injection synthesis of metal-doped Ag2S nanocrystals: A novel multifunctional approach for cancer therapy, antibacterial strategies, and antioxidant defense(Springer, 2026) Ulusu, Funda; Ozel, Sultan Suleyman; Sarilmaz, Adem; Ulusu, YakupThis pioneering study presents the synthesis and comprehensive evaluation of bare and metal-doped Ag2S nanocrystals (NCs) as multifunctional agents with potential applications in antibacterial, antioxidant, and anticancer therapies. The incorporation of manganese, nickel, cobalt, and zinc into Ag2S NCs resulted in a notable enhancement of their bioactivity, representing a novel approach in nanomaterial design. The antibacterial assessments revealed that Mn:Ag2S NCs were the most potent candidate, exhibiting exceptional activity against S. aureus and E. coli, with the lowest MIC values recorded at 1.28 mg/mL and 1.08 mg/mL, respectively. The antioxidant studies demonstrated that the Mn:Ag2S NCs exhibited remarkable free radical scavenging and ferric reducing capacities, with the lowest IC50 values (22.69 mu g/mL for DPPH and 61.31 mu g/mL for FRAP) underscoring their potential to mitigate oxidative stress. Importantly, cytotoxicity assays revealed that Ni:Ag2S and Mn:Ag2S nanocrystals selectively inhibited the proliferation of human colon cancer cells (HT-29), achieving IC50 values of 61.51 mu g/mL and 90.12 mu g/mL, respectively. Furthermore, these NCs demonstrate reduced toxicity towards mouse fibroblast cells (L929). This selective cytotoxicity indicates the potential of these agents in targeted cancer therapies, thereby reducing damage to healthy tissues. To the best of our knowledge, this is the first study to systematically explore the synergistic effects of metal doping on the multifunctional properties of Ag2S NCs. These findings provide a robust basis for further in vivo studies and offer new avenues for the development of safe and effective nanomaterials in biomedical applications, particularly as antimicrobial, antioxidant, and anticancer agents.Öğe Acute Music-Frequency Exposure Modulates Salivary Stress and Neurotrophic Markers in Young Adults: A Randomized Controlled Trial(Wiley, 2026) Bozok, Ummu Gulsen; Ozcan, Gulbahar Boyuk; Bayraktar, Bulent; Ozen, DogukanBackground: The exam period is a period full of intense stress and anxiety that deeply affects cognitive and physiological responses for university students. Listening to music has the potential to protect cellular health and alleviate the negative effects of stress by affecting individuals' mood, and cognitive functions. This study aimed to investigate the differential effects of 528 and 432 Hz music frequencies on salivary BDNF, CREB, and GRP78 levels in young adults, along with their association with cognitive performance under exam-related stress. Methods: A total of 162 healthy university students were randomly assigned to three groups: no music (control), 528 Hz instrumental music, and 432 Hz instrumental music. Participants listened to music for 20 min, after which saliva samples were collected and analyzed for brain-derived neurotrophic factor (BDNF), glucose-regulated protein 78 (GRP78) and cyclic AMP response element-binding protein (CREB) levels using ELISA. Cognitive performance was assessed using the Stroop word-color test administered by medical doctor. Results: Exposure to 528 Hz music significantly increased salivary BDNF (3.84 [2.76-4.13]) and CREB levels (1.5 [1.38-1.59]) compared to control (p < 0.05), whereas GRP78 levels were elevated in the 432 Hz group (0.51 [0.47-0.58]) (p < 0.05). No significant differences were observed between groups in Stroop test performance. Conclusion: These findings suggest that specific music frequencies elicit distinct biological responses under exam-related stress, even in the absence of immediate cognitive performance differences. Salivary neurotrophic and stress-related biomarkers may offer valuable non-invasive insights into music's neuromodulatory effects.Öğe Gastrointestinal stability and bioactivity of propolis from diverse origins(Springer, 2026) Can, Zehra; Celebi, Zeynep Berin; Tunca, Erol; Kolayli, Sevgi; Sevin, Sedat; Tutun, HidayetPropolis is a chemically complex bee product whose biological properties depend on its botanical and geographical origin. However, little is known about how gastrointestinal digestion affects its phenolic profile and bioactivity. In this study, twelve propolis samples from eight countries were evaluated for phenolic and flavonoid contents, antioxidant capacity (FRAP, ABTS+center dot), and urease inhibition before and after simulated gastric digestion. RP-HPLC-PDA identified 26 phenolic compounds showing substantial compositional diversity. Turkish Bolu propolis retained the highest post-gastric FRAP value, while several samples (BBP, AFP) maintained or enhanced urease inhibition. PCA and HCA highlighted origin-dependent differentiation, identifying digestive stability as a key variable for functional potential.Öğe Structural condition assessment of the Bamsı Beyrek observation terrace in Bayburt, Türkiye, on autonomous updated FEMs(Springer, 2026) Ergun, Mustafa; Tayfur, Bilal; Gunes, ErdiThis study involves detailed numerical and experimental investigations to assess the current structural condition of the Bams & imath; Beyrek steel observation terrace in Bayburt, T & uuml;rkiye. The numerical dynamic characteristics of the structure were obtained by free vibration analysis conducted on the preliminary finite element model, while the experimental ones were determined through ambient vibration testing. The ultimate finite element models representing the actual state of the structure were developed through the model updating process based on the principle of minimizing the differences between numerical and experimental dynamic characteristics via the Teaching-Learning Based Optimization Algorithm. Load types and their characteristic values, potentially impacting the observation terrace during its service life, were identified according to national and international code standards. The internal forces obtained from the analysis conducted on the updated model under the influence of these loads were combined using various load combinations. The structure was then statically and dynamically checked based on the most critical responses calculated from these combinations. Structural responses are evaluated based on distributions in PMM ratios on the structure, PMM ratios of all elements according to the combination that causes the most adverse values, and maximum displacements. Consequently, considering all the findings obtained from the assessments conducted on the finite element model, which reflects the current state of the observation terrace under various loads, it has been concluded that the structure is statically and dynamically reliable and does not require any repair or strengthening procedures.Öğe Depth-dependent predictability of soil temperature under Mediterranean climatic conditions: a frequency-based perspective(Springer Wien, 2026) Guleryuz, Didem; Yildirim, Umit; Guler, CuneytSoil-temperature predictability is inherently depth-dependent because atmospheric forcing is progressively attenuated and transformed into smoother, lower-frequency thermal dynamics with increasing depth. Under Mediterranean climatic conditions, where pronounced seasonality and strong surface forcing coexist, this depth-dependent transformation provides an informative basis for evaluating model behaviour. This study examines soil-temperature prediction at depths of 5, 10, 20, 50, and 100 cm using a multivariate dataset comprising 5,285 retained daily observations from the Mersin meteorological station on T & uuml;rkiye's eastern Mediterranean coast. Precipitation, air temperature, relative humidity, wind speed, and evaporation were used as predictors. Support vector regression, random forest, and LightGBM were evaluated using R & sup2;, RMSE, and MAE. All three models performed strongly in the near-surface layers, with test R & sup2; values ranging from 0.948 to 0.954 at depths of 5-20 cm. Predictive performance declined with increasing depth as short-period variability weakened and the thermal signal became smoother and more seasonally structured. RF and LightGBM showed a greater numerical decline at 50-100 cm, whereas SVR achieved test R & sup2; values of 0.923 at 50 cm and 0.847 at 100 cm; however, inter-model differences remained modest and were interpreted descriptively. Lomb-Scargle spectral analysis, applied using the actual observation dates, indicated that short-period variability became relatively less pronounced with depth while seasonal-scale and low-frequency components remained prominent. Overall, the findings suggest that soil-temperature prediction should be interpreted in relation to depth-dependent temporal signal characteristics rather than as a search for a universally superior algorithm.Öğe Problem posing on vectors in space: preservice teachers' perspectives(Springer, 2026) Ergin, Ayda Nur; Ozturk, Mesut; Aydin, Tuba AgirmanThis study examines preservice elementary mathematics teachers' problem-posing processes related to vectors in space. Adopting a qualitative case study design, the problem-posing process was analyzed by treating the phases of orientation, connection, generation, and reflection as analytic units, focusing on the cognitive, linguistic, and reasoning-based actions exhibited at each phase. The findings reveal that preservice teachers experience considerable difficulties in establishing meaningful connections between mathematical structures and real-life contexts, particularly when posing vector problems in three-dimensional environments. In addition, causal attribution processes became salient during the reflection phase, with participants frequently explaining their successes and difficulties by referring to their conceptual understanding, prior experiences, and perceived competence. The results offer implications for the design of theory-based learning environments that support problem-posing processes in mathematics teacher education, particularly for advanced mathematical topics.Öğe The effect of digital and traditional methods on learning and retention in preschool education: a comparison of virtual reality, augmented reality, web-based, and manipulative materials(Springer, 2026) Tutkun, CansuThe pedagogical use of digital technologies in early childhood education is increasingly prevalent today. Augmented reality, virtual reality, and web-based content have the potential to make children's learning processes more interactive and lasting. In this context, the study compared the effects of different teaching methods presented with augmented reality, virtual reality, web-based, and manipulative (traditional) materials on children's learning and retention levels. In the quasi-experimental study, a total of 400 children attending preschool education institutions in Bayburt, Turkey, were divided into four different groups and evaluated using a "pre-test-post-test-retention test" model. The results revealed that the virtual reality group achieved the highest scores in both learning and retention levels, followed by the augmented reality and web-based groups, while the manipulative group demonstrated the lowest performance. In addition, the virtual reality environment was evaluated by children as the most enjoyable and satisfying method, and children in this group were the most willing to use the training again. These results show that digital technologies such as virtual and augmented reality in preschool education should be evaluated as effective tools in terms of achieving pedagogical goals and increasing children's interest in learning.Öğe Investigation of structural, optical and optoelectronic properties of eumelanin pigment(Springer Heidelberg, 2026) Aksoy Pehlivanoglu, Seval; Bayram, SinanIn this work, the structural, morphological and optical properties of the eumelanin film fabricated on an FTO substrate were first investigated. Then, the effects of illumination intensitiy on the optoelectronic properties of the device fabricated on p-Si substrate (Eumelanin/p-Si) were investigated. The deposited film was identified as polycrystalline from the XRD pattern. The crystallite size was found to be approximately 13 nm. Surface morphology analysis of the film was carried out using atomic force microscopy (AFM) measurements. The surface roughness value (Rq) of the film was determined to be 55.7 nm. The film's transmittance in the visible region is approximately 83%. The average refractive index in the visible region was calculated to be 1.39. The E-g value of the eumelanin film was determined using both the Tauc technique and the Kubelka-Munk function. The direct and indirect optical bandgaps of eumelanin were calculated using both the Tauc method and the Kubelka-Munk function. The calculated direct and indirect optical bandgap values are, respectively, 2.79 eV and 1.96 eV for the Tauc method, and 2.65 eV and 1.79 eV for the Kubelka-Munk method. The electronic parameters of Eumelanin/p-Si heterostructure were derived from its I-V characteristics. The charge transport mechanisms controlling the diode behavior of the eumelanin/p-Si structure were investigated and analyzed using the power law relationship I proportional to V-m. I-V measurements performed at various illumination intensities indicated that the device exhibited photoconductive behavior. All the results obtained from this study demonstrate the potential of eumelanin/p-Si device to be used in photonic applications.Öğe Integrating artificial intelligence into preservice teacher education: enhancing AI literacy and digital material design competency(Springer, 2026) Gulen, Hilal Nur; Kucuk, SevdaThe rapid advancement of Artificial Intelligence (AI) has transformed educational tools and practices. Integrating AI into instruction supports complex thinking, enriches teaching, and helps educators in material creation and visualization. Therefore, it is essential to equip both students and educators with AI literacy and digital material design competencies in order to support pedagogically sound and ethically responsible instructional practices. Within this context, the present study examines the extent to which an AI-integrated instructional technology course influences pre-service teachers' AI literacy and digital material design competencies, as well as their perceptions and experiences of learning within an AI-integrated instructional environment. Using a mixed-methods approach, 50 pre-service social studies teachers (41 female, 9 male) participated in a semester-long course. Data were collected through the Artificial Intelligence Literacy Scale, Digital Material Design Competency Scale, and semi-structured interviews. Paired sample t-tests indicated significant gains in both AI literacy and digital material design competencies, with large effect sizes. Qualitative and quantitative findings showed that AI tools not only improved technical abilities but also enhanced pedagogical thinking. The study highlights the importance of AI-integrated curricula in preparing future teachers for modern educational challenges.Öğe A NIKOM-Based Conceptual Framework for Spiritual Counseling Services in Turkey: Toward an Intervention Model(Springer, 2026) Cinici, MuratSpiritual counseling has expanded rapidly in Turkiye over the past two decades. Hospitals, prisons, family guidance offices, eldercare facilities, disaster-response systems, and addiction recovery programs now host spiritual counselors as part of routine care. The methodological foundation of these services, however, remains underdeveloped. Using a conceptual review and theoretical integration approach, this article proposes-but does not empirically test-a framework that links spiritual counseling practice in Turkiye to the Intention Code Model (NIKOM), a recently formulated cognitive model that conceptualizes mental life through if-then schemas (codes), their activation, and their alignment with bodily systems. The article reviews the institutional landscape of spiritual counseling in Turkiye, situates NIKOM among adjacent cognitive models, and shows how core Islamic concepts-tawakkul, sabr, shukr, tawba, and dhikr-can be interpreted as functions relevant to counseling practice. A standardized five-stage intervention template is proposed and applied to six service domains. The article closes by offering five testable propositions, considering ethical limits, and articulating concrete referral criteria. The proposed framework is theoretically grounded and empirically testable; clinical efficacy is not claimed.Öğe Beyond Algorithms: Unveiling the Intersection of AI Ethics, Citizenship Education, and Social Studies(Springer International Publishing Ag, 2025) Yetisensoy, OkanThe rapid rise of artificial intelligence (AI) in recent years has led to various positive transformations in everyday life. However, this rise has also brought about the emergence of some ethical issues that raise concerns in society. Examples of these ethical issues include the manipulative or harmful use of AI, privacy concerns, bias, discrimination, and lack of transparency and accountability. AI ethics, on the other hand, represent a set of guiding principles that stakeholders should adopt to ensure the responsible development and utilization of AI technologies. Considering that young people are potential users and developers of AI, teaching them these principles from an early age can be seen as a natural part of citizenship education. Thus, incorporating AI ethics-related content into the curriculum of various K-12 courses can be regarded as an effective approach. This chapter argued that social studies, with its focus on fostering effective citizens for the future, will emerge as a crucial application area for this approach. At this point, the relevant study aims to explore the intersections between AI ethics, citizenship education, and social studies. It is believed that the study will make a significant contribution to the literature by revealing the new dynamics created by AI in citizenship education and demonstrating the potential role that the social studies curriculum can play in this regard.Öğe SURVEILLANCE OR SUPPORT? A SYSTEMATIC LITERATURE REVIEW OF ARTIFICIAL INTELLIGENCE SUPPORTED PROCTORED ONLINE EXAMS(Anadolu Univ, 2026) Ustun, Aysin Gaye; Kayali, Bunyami; Yavuz, Mehmet; Bozkurt, ArasProctored online exams have become widespread, especially after COVID-19, increasing exam security and efficiency. In recent years, artificial intelligence developments have increased these systems' importance by expanding their use. Accordingly, this study aims to provide an in-depth understanding of the conceptual structure of artificial intelligence-supported proctored online examination (AI-SPOE) research. Systematic literature review and text mining were used as methods. Thirty-two studies in Scopus and Web of Science databases were analyzed according to the PRISMA technique. While all the studies were examined in the context of content analysis, abstracts and keywords of the relevant studies were analyzed by text mining. The current study found it effective in increasing academic integrity and exam security, but problems such as privacy violations, exam anxiety, and algorithmic biases were encountered. Although methods such as biometric verification and behaviour analysis successfully detect cheating, technical difficulties, and false positives negatively affect the user experience. In the future, more inclusive designs, transparent algorithms, and alternative evaluation methods are suggested. In conclusion, the study emphasizes the potential of AI-SPOE systems and highlights the importance of ethical and technical improvements.Öğe Psychometric Validation of the Turkish Version of the Personalized Psychological Flexibility Index (T-PPFI) in Disaster Search and Rescue Volunteers(Asoc Analisis Comportamiento, 2026) Cinar, Oznur; Cengiz, EkremThis study aimed to perform a cross-cultural adaptation of the English version of the Personalized Psychological Flexibility Index into Turkish (T-PPFI). It was conducted among 604 disaster search and rescue volunteers who participated in the 2023 Kahramanmara & sect; earthquakes in Tiirkiye. Exploratory factor analysis supported a three-factor, 15-item structure, and confirmatory factor analysis indicated good fit for the three-factor model. Convergent and divergent validity were supported by a positive correlation with the Comprehensive Assessment of Acceptance and Commitment Therapy Processes (CompACT) and negative correlations with the Acceptance and Action Questionnaire-II (AAQ-II) and the Depression Anxiety and Stress Scales-21 (DASS-21). The T-PPFI showed acceptable internal consistency (total score a= .727; w= .712) and high test-retest reliability over 14 days (r= .962). Gender measurement invariance analyses supported comparability of T-PPFI scores across men and women. Hierarchical regression analyses provided evidence for the incremental validity of the T-PPFI beyond AAQ-II and CompACT in predicting DASS-21 outcomes, and higher-order EFA supported construct-level discriminant validity. The findings suggest that the 15-item T-PPFI is a reliable and valid measure of psychological flexibility in Turkish disaster search and rescue volunteers.Öğe CMTS: An inorganic hole-transport material for efficient and stable perovskite solar cells through surface defect passivation(Springer, 2026) Sari, Fahriye; Ozel, Sultan Suleyman; Ozel, Faruk; Kus, Mahmut; Wilton, Richard HallA major challenge in PSCs lies in the carrier transport losses induced by band misalignment and elevated series resistance, which adversely impact the fill factor and device stability, ultimately restricting the overall power conversion efficiency. Due to their tunable band gaps, low fabrication cost, strong light-harvesting capability, adequate carrier lifetime, chemical stability, and environmentally benign nature, chalcogenide perovskites have emerged as highly promising materials for optoelectronic applications. In this study, the quaternary semiconductor nanostructure Cu2MnSnS4 (CMTS) was synthesized via a simple and cost-effective hot-injection method and investigated as an alternative inorganic hole transport layer (HTL) candidate. Indium tin oxide-based perovskite solar cells without any metal oxide interlayer achieved a remarkable PCE of 9.87% and retained more than 92% of their initial efficiency after 720 hours, demonstrating enhanced stability. These findings highlight the critical role of cation-anion interactions in improving device stability and underscore the importance of developing innovative, low-cost, and efficient inorganic HTL materials for the commercial advancement of perovskite solar cells.Öğe The moderating effects of geopolitical risks on sustainable development through economic complexity and renewable energy consumption in 25 oil-producing countries(Springer, 2026) Ongan, Serdar; Ozdemir, Dilek; Imamoglu, Ilyas Kays; Isik, CemConflicts in controlling or using natural resources, arising from geopolitical risks (GPR), which have become a new normal today, can damage natural ecosystems and threaten sustainable development. In this context, GPR can turn the positive impact of supporting independent variables on sustainable development (SD) into a negative one. This research investigates the moderating effects of GPR on SD through renewable energy consumption (REN) and economic complexity (EC) in 25 oil-producing countries with relatively higher oil-reserve-related risks between 2000 and 2021. The panel quantile regression analysis reveals. (i) While using REN individually improves SD in countries with high SD (in the 80th and 90th quantiles), this improving effect turns to a worsening effect due to its interaction with GPR, which shows the moderating impact of GPR. (ii): While EC individually improves SD across all quantiles, these improving effects persist in countries with low SD (in the 10th, 20th, 30th, and 40th quantiles) even when complexity interacts with GPR, showing that GPR has no moderating impact on SD. Therefore, policymakers should investigate why the interaction of REN with GPR worsens SD in highly sustainable countries and redevelop regulatory renewable energy policies accordingly.Öğe Multi-Pathway Renoprotection by Betanin Against Docetaxel Nephrotoxicity: Modulation of Inflammation, ER Stress, Apoptosis, and Ferroptosis(Wiley, 2026) Celbek, Busra Suzen; Akaras, Nurhan; Simsek, Hasan; Mutlu, Huseyin; Kizil, Hamit Emre; Kandemir, Ozge; Kandemir, Fatih MehmetDocetaxel (DTX), a cornerstone chemotherapeutic agent, has its clinical utility significantly limited by dose-dependent nephrotoxicity. This study investigated the multi-pathway renoprotective mechanisms of betanin (BTN), a natural antioxidant derived from beetroot, against DTX-induced kidney injury. Male Wistar rats received DTX (30 mg/kg, i.p., single dose) with or without BTN (100 mg/kg/day, p.o.) for 7 days. DTX induced severe renal dysfunction with elevated serum urea and creatinine, and significant oxidative stress characterized by increased MDA and decreased GSH, GPx, SOD, and CAT. Molecular analysis demonstrated widespread upregulation of pro-inflammatory (NF-kappa B, TNF-alpha, IL-1 beta), endoplasmic reticulum stress (PERK, ATF6), pro-apoptotic (Caspase-3, Bax, Apaf-1), and pro-ferroptotic (PTGS2, TfR1) mediators, with concurrent downregulation of protective Bcl-2 and GPx4. Histopathological examination revealed extensive tubular injury, while immunohistochemical analysis showed markedly increased kidney injury marker KIM-1 and decreased aquaporin-1 expression. Remarkably, BTN co-administration significantly attenuated all biochemical, molecular, and structural derangements, restored tissue architecture, and normalized KIM-1 and AQP-1 expression. In conclusion, betanin provides robust, multi-pathway renoprotection against docetaxel-induced nephrotoxicity by concurrently targeting oxidative stress, inflammation, ER stress, apoptosis, and ferroptosis.Öğe Exploring the ımpact of metal doping and alternative electrodes on the performance of dye-sensitized solar cells(Springer, 2026) Caliskan, Berrak; Sayan, Enes; Igman, ErdalThis study explores the synthesis and characterization of metal-doped TiO2 thin films for applications in dye-sensitized solar cells (DSSCs). Titanium dioxide (TiO2) films were doped with various metal ions such as Ag+, Zn2+, Fe3+, and Co2+, to enhance the photoelectrochemical properties of the photoanode. The films were characterized using various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis spectroscopy, and X-ray photoelectron spectroscopy (XPS). The doping process was found to influence the morphology, surface area, and optical properties of the TiO2 films, resulting in enhanced light absorption, particularly in the visible range. The effects of metal doping on the performance of the DSSCs were evaluated, showing that Co2+ and Ag+ doping resulted in improved efficiency compared to undoped TiO2, with the Co2+-doped TiO2 achieving the highest power conversion efficiency of 2.85%. Additionally, the incorporation of reduced graphene oxide (rGO) as a counter electrode demonstrated a significant enhancement in DSSC performance, even surpassing traditional platinum-based counter electrodes. The results suggest that metal doping and rGO incorporation offer promising strategies for improving DSSC efficiency. This study highlights the potential of metal-doped TiO2 photoanodes and rGO counter electrodes in advancing the development of cost-effective, high-performance DSSCs for sustainable solar energy applications.Öğe The effect of existing damage on the seismic performance of a historical masonry structure: a site-specific assessment(Springer, 2026) Tayfur, Bilal; Tunca, Osman; Artar, Musa; Carbas, SerdarThis study comprehensively evaluates the structural integrity and seismic performance of a historic masonry mosque, exhibiting significant settlement cracks, through an integrated approach combining field measurements and advanced numerical analyses. The Operational Modal Analysis (OMA) conducted to determine the dynamic characteristics of the structure. Field measurements revealed that the environmental vibrations originating from a nearby tram line causes significant amplitude incrase in one of the main columns. The dynamic characteristics of the structure obtained from field experiments are used to calibrate the numerical model via the Particle Swarm Optimization Algorithm. The calibrated numerical model, taking into account the existing cracks in the structure using contact elements, was subjected to nonlinear analysis in the time domain under 11 site-specific ground motion records selected in accordance with the procedures of the Turkish Building Seismic Code. This analysis examined the seismic performance and damage mechanisms of the structure. The findings revealed that while existing settlement cracks contribute to seismic energy dissipation through frictional sliding and gap opening mechanisms, they may also serve as potential failure initiation points under strong ground motions. This study's integrated approach, combining dual-purpose OMA application and explicit crack modeling with contact elements, constitutes a novel methodological framework for the realistic seismic assessment of historic masonry structures with pre-existing damage.Öğe Comparative thermal and hydraulic performance of Type-22 panel radiators under continuous and pulsating flow(Pergamon-Elsevier Science Ltd, 2026) Koksal, Huseyin; Ceviz, Mehmet Akif; Muratcobanoglu, Burak; Mandev, EmrePulsating water-side flow has been proposed as a radiator control strategy to enhance heat emission at low supply temperatures, yet device-level studies rarely quantify thermal gains together with hydraulic costs under matched baselines. This study experimentally investigates the coupled thermal and hydraulic response of a PCCP Type-22 panel radiator operated under continuous and on-off pulsating flow regimes. A dedicated test loop was developed using a temperature-controlled hot-water tank (50 degrees C setpoint) and an Arduino-based driver to impose repeatable pulsation, while measuring inlet/outlet temperatures, instantaneous flow rate, pump electrical energy, and spatiotemporal surface temperatures via infrared thermography. The results show that increasing the continuous flow rate provides the highest absolute heat output, but at the cost of increased pumping energy. In contrast, pulsating operation improves the thermal-hydraulic balance by increasing heat delivery relative to the reference case while reducing pump energy consumption. Among the tested pulsating cases, short-period pulsation produced the most favorable behavior by maintaining a warmer and more spatially stable radiator surface. Longer off-periods promoted deeper surface cooling, reduced the effective emitting area, and weakened the thermal benefit of pulsation. Infrared thermography confirmed that the pulsation period strongly affects surfacetemperature uniformity and temporal stability. Overall, short-period on-off pulsation emerges as the most favorable operating mode when the objective is to increase heat delivery while lowering pumping energy in PCCP-type radiators.
