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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14411/18
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Article Optimizing Drone-Based Humanitarian Relief in Post-Disaster Scenarios: A Hybrid MCDM and Maximum Coverage Approach(Springer Heidelberg, 2026-05-02) Vural, DanismentThis study proposes a novel hybrid decision-making framework that integrates expert-driven supply prioritization via the Stepwise Weight Assessment Ratio Analysis (SWARA) method with an operationally constrained Maximum Coverage Problem (MCP) model to optimize drone-based humanitarian logistics in post-disaster scenarios. Grounded in a real-world case study of the 2023 Kahramanmaraş earthquake, the model systematically elicits expert preferences to rank critical supplies such as food, medical items, and cold chain products, and embeds these weights directly into a constrained MCP formulation. The model incorporates drone-specific operational limits, including battery consumption, payload capacity, and round-trip feasibility, to ensure realistic deployment strategies. Results show that scenario configurations with four to five strategically located drone bases, each equipped with four to five drones, can increase the achieved priority-weighted delivered quantity by up to 35-40% compared to minimal base-drone configurations within the proposed model framework. Moreover, the proposed framework improves responsiveness by prioritizing urgent deliveries and supporting more timely allocation decisions under operational constraints. Unlike traditional MCP approaches that rely on static weights, this method offers a context-sensitive and scalable optimization model informed by field expertise. The findings underscore the potential of structured expert-based weighting combined with operational optimization to enhance the efficiency and responsiveness of drone-assisted disaster relief systems.Article Global De-Democratization and Women’s Political Empowerment in the 2000s(Pergamon-Elsevier Science Ltd, 2026-07) Ertan, Senem; Keysan, Asuman ÖzgürSince 2000, democratic backsliding led to changes in the gender regime, a deterioration in gender equality, and a decline of women's empowerment demonstrated in many country studies and small-N comparisons. Given the lack of large-N cross-national analyses, this paper seeks to close the gap by examining the impact of dedemocratization on women's political empowerment by comparing 162 countries. The findings highlight that lower levels of democracy are associated with lower levels of women's political empowerment. Indeed, not only cross-national, but also within-country changes in democracy levels have substantial short-term and long-term effects on women's political empowerment. Although securing representative democracy with free political parties, free and fair elections, or an effective parliament is important to politically empower women, this study demonstrates that women's political empowerment is sustained in countries where the rule of law and participatory democratic rule are strongly consolidated.Article Development and Validation of the Athlete Food Insecurity Scale (AFIS)(MDPI, 2026-04-10) Yıldırım, Gonca; Baş, Murat; Çetiner, Özlem; Sünbül, ÖnderBackground/Objective: Athletes' dietary needs are influenced by the physiological demands of their sport, so the impacts of disrupted food access may vary from those experienced by the general population. This study aimed to develop and validate the Athlete Food Insecurity Scale (AFIS), a sport-specific tool designed to measure food insecurity in athletes. Materials and Methods: The study included 500 young adult athletes from 18 different sports disciplines. The sample was divided for exploratory factor analysis (n = 300) and confirmatory factor analysis (n = 200). Standard procedures for scale development were followed, including content validity assessment, construct validity testing, convergent validity analysis, and reliability evaluation. Results: The final 23-item scale demonstrated a four-factor structure including performance changes, coping strategies, basic nutritional needs, and physical access restraints. Factor loadings ranged from 0.344 to 0.956, item-total correlations from 0.513 to 0.781, and Cronbach's alpha coefficients from 0.827 to 0.937. Confirmatory factor analysis supported the modified model with acceptable fit indices (chi(2)/df = 2.41, RMSEA = 0.080, TLI = 0.900, CFI = 0.910), and standardized factor loadings ranged from 0.53 to 0.89 (p < 0.05). Subscale scores differed significantly across Household Food Security Survey Module food security categories, supporting convergent validity. Conclusions: The AFIS demonstrates strong psychometric properties and may provide a sensitive tool for identifying and monitoring sport-specific food insecurity among athletes.Article Rethinking the Second Life of Post-Disaster and Post-Conflict Temporary Housing(Ubiquity Press Ltd, 2026) Ay, Bekir Özer; Dino, İpek Gürsel; Akdede, NilProviding temporary housing (TH) units after natural hazards and social conflicts is often an urgent necessity. Beyond their initial configuration, the second life of these units is crucial, given their temporary nature. Despite growing interest in second-life strategies, many TH units and associated infrastructure remain unused or inefficiently managed after their initial deployment. Second-life strategies are presented for post-disaster and post-conflict (PDPC) TH units and settlements in Türkiye, using two case studies-the 2011 Van earthquakes and Syrians under temporary protection-and expert insights from the Disaster and Emergency Management Presidency of Türkiye (Afet ve Acil Durum Yönetimi Başkanlığı-AFAD). Athree-step methodology was employed, including a literature review, semi-structured expert interviews and hybrid deductive-inductive thematic analysis. Findings reveal that second-life outcomes are largely shaped by policy gaps, operational conditions, tenure constraints, institutional decisions and user practices rather than by design-based circular approaches. The proposed framework provides practical guidance for policymakers and practitioners in Türkiye and other crisis-prone contexts to improve resource efficiency and integrate second-life planning into preparedness and recovery processes.Article Quantum-Corrected Thermodynamics of Conformal Weyl Gravity Black Holes: GUP Effects and Phase Transitions(Academic Press Inc., 2026-07) Sakallı, İzzet; Sucu, Erdem; Dengiz, SuatWe investigate the thermodynamic properties of black holes in Conformal Weyl Gravity (CWG) using the Mannheim-Kazanas solution, with particular emphasis on quantum corrections that become significant near the Planck scale. Our analysis employs the Hamilton-Jacobi tunneling formalism to derive the Hawking temperature, revealing explicit contributions from the conformal parameters beta, gamma, and k that lead to substantial deviations from Schwarzschild black hole behavior. We incorporate quantum gravitational effects through the Generalized Uncertainty Principle, demonstrating systematic suppression of thermal radiation in the near-Planckian regime. Using an exponentially corrected entropy model, we compute the complete spectrum of QC thermodynamic potentials, including internal energy, pressure, heat capacity, and free energies. Our heat capacity analysis shows divergence behavior that separates stable and unstable regions, indicating possible thermodynamic transitions controlled by the scale-dependent parameter gamma. The Joule-Thomson expansion analysis shows distinct cooling and heating regimes with inversion points that shift systematically with CWG parameters, capturing QC phase transitions absent in general relativity. We also examine gravitational redshift in CWG geometry, finding complex radial dependence that highlights modifications compared to the Schwarzschild case, although redshift alone cannot observationally distinguish CWG from Einstein's theory. Our results demonstrate that CWG offers a consistent framework for studying black hole thermodynamics beyond general relativity, with quantum corrections modifying phase structures in the near-Planckian regime, though these effects are not expected to yield direct observational consequences.Article From Facial Expressions to Thermal Sensation: POMS-Validated AI-Based Mood Estimation Driving Psychology-Adaptive HVAC Control(Elsevier Science SA, 2026-06) Saleh Saleh, Yousif Abed; Sümer, Mustafa Erdi; Saleh, Yousif Abed Saleh; Lotfi, Bahram; Turhan, Cihan; Özbey, Mehmet FurkanThe psychological state of building occupants plays a critical role in how thermal environments are perceived and experienced, yet conventional Heating, Ventilation, and Air Conditioning (HVAC) control strategies largely ignore this factor. Current systems typically focus on environmental and personal parameters, overlooking the influence of mood state on thermal comfort. This omission can lead to suboptimal comfort levels, decreased occupant satisfaction, and inefficient energy use. Integrating psychological feedback into the HVAC control has the potential to transform indoor climate management into a truly occupant-centric process. To this aim, this study presents a novel framework that employs artificial intelligence (AI) and image processing together to estimate occupants' mood states in real time. Facial expressions are analysed using a deep learning-based computer vision model, and the resulting mood predictions are validated with the Profile of Mood States (POMS) questionnaire to ensure accuracy and reliability. Validated mood data directly informs the HVAC setpoint adjustments, enabling psychology-adaptive control that responds dynamically to occupants' current mood states. Moreover, the system operates in real time, combining low-latency image analysis with adaptive control algorithms to continuously align thermal conditions with validated mood estimations. Additionally, implementing mood-driven HVAC control shows potential for enhancing perceived comfort while improving energy efficiency. By bridging the gap between psychological state assessment and environmental control, this research contributes to the advancement of intelligent building systems, paving the way for more responsive, energy-conscious, and human-centered indoor environments.Article Techno-Economic assessment of PV, wind, and geothermal energy hybrid system for green hydrogen production: A case study in Denizli, Türkiye(Elsevier Ltd, 2026-05) Devrim, Yılser; Nalbant Atak, Yagmur; Erdogan, Anil; Atak, Yagmur NalbantThis study presents a scenario-based techno-economic assessment of grid-connected green hydrogen production in Denizli, Türkiye using a hybrid renewable energy system integrating photovoltaic (PV), wind turbine (WT), and geothermal power plant (GP) with a proton exchange membrane electrolyzer (PEMEL). A demand-driven electrolyzer sizing approach is adopted, and four configurations (PV–WT–GP, PV–GP, WT–GP, and PV–WT) are evaluated under three hydrogen production levels (750, 1000, and 1500 kg/day), resulting in twelve scenarios. An energy balance model simulates operation and grid interaction, while techno-economic performance is evaluated via net LCOH. LCOH ranges from 8.8 to 18.8 €/kg H2, lowest for PV–WT–GP at low output. Higher capacity increases dependence on grid and costs, indicating diseconomies of scale. Sensitivity analysis shows electricity import/export prices strongly affect LCOH, especially at larger scales, highlighting the role of hybrid design and geothermal integration. © 2026 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article Structure–Property–Performance Relationship of Graphene Oxide Modified Composite Membranes for Anion Exchange Membrane Electrolyzers(John Wiley and Sons Inc, 2026-04) Devrim, Yılser; Altinisik, Hasan; Abay, Ogün; Özalp, Ercan; Kim, Hern; Önel, Nisa GökçenIn this study, graphene oxide (GO)-modified poly (phenylene oxide, PPO) anion exchange membranes (F/GO) were developed forapplication in anion exchange membrane electrolyzers (AEMELs). The incorporation of GO enhanced membrane hydration, ion-exchange capacity, and hydroxide-ion conductivity, resulting in an ~15% increase in current density at 2.0 V and 80°C (0.551 A/cm2) compared with the pristine membrane (0.480 A/cm−2). The F/GO membranes also showed enhanced hydrogen productionrates and an HHV-based energy efficiency of 76% at 0.5 A/cm2 and 80°C. These results underscore the potential for F/GO mem-branes in scalable AEMEL applications. Mechanical and alkaline stability tests confirmed robustness under harsh conditions.These findings demonstrate that the incorporation of GO provides a simple, scalable, and potentially lower-cost modificationstrategy compared with highly engineered polymer architectures, while also improving overall electrolyzer performance, high-lighting the potential of GO-modified membranes for practical hydrogen production in AEMEL systems.Article Bayesian polarimetric multi-source direction-of-arrival estimation for transient astronomy with sparse radio interferometric subarrays(Elsevier B.V., 2026-05) Tank, Fatih; Zeghdoudi, HalimModern radio interferometers are increasingly challenged by fast transient events, complex radio-frequency interference (RFI), and observing conditions in which near-field and far-field emitters may coexist. Although classical direction-of-arrival (DOA) techniques can achieve high angular resolution, they are often developed for specific array geometries, tend to focus on single-source settings, and usually provide little information about uncertainty. Imaging-based methods, while powerful, are computationally demanding and can introduce delays that are not well suited to real-time transient astronomy. In this work, we propose a Bayesian, polarization-aware framework for multi-source DOA estimation in arbitrary radio interferometric arrays. Starting from baseline-level covariance modeling and polarization-sensitive phase information, we build a probabilistic formulation that jointly infers source direction, polarization state, and, when relevant, source range. Because interferometric phase is inherently wrapped, uncertainty is modeled explicitly using circular statistical distributions, and posterior inference is carried out through a variational Bayesian scheme that remains computationally efficient. Compared with deterministic or purely data-driven approaches, the proposed method offers a more physically grounded and statistically interpretable alternative. It incorporates array geometry, polarization structure, and prior astronomical knowledge directly into the inference process, while also delivering calibrated uncertainty estimates for source localization. Simulations using realistic LOFAR and SKA-Low configurations show robust multi-source separation, stable performance across wide bandwidths, and improved resilience in low signal-to-noise and near-field conditions. Overall, the proposed framework enables imaging-free, uncertainty-aware localization of fast radio bursts, solar radio emission, and terrestrial RFI. It provides a statistically principled and computationally practical route toward real-time transient localization in next-generation radio observatories. © 2026 The Authors.Article Simulation-Based Optimization of HVAC Systems in Aging Educational Facilities: Addressing IAQ Challenges Through Retrofitting(MDPI, 2026-03-20) Saleh, Yousif Abed Saleh; Turhan, Cihan; Turhan, BurcuIndoor air quality (IAQ) in educational buildings plays a critical role in the health, cognitive performance, and well-being of occupants. Aging university facilities often rely on outdated ventilation systems that are not designed to meet current demands or respond to dynamic occupancy levels. This study investigates the performance and feasibility of various advanced ventilation strategies in comparison to an existing balanced mechanical ventilation (BMV) system in a university classroom accommodating 100 students. Using a Dynamic Building Energy Simulation Program, simulations were conducted to evaluate IAQ (using CO2 levels), energy consumption, and thermal comfort under three retrofitting scenarios: BMV, demand-controlled ventilation (DCV), and hybrid ventilation combining natural and mechanical airflow. The simulations indicate that DCV cuts annual HVAC energy use by 33% relative to the baseline, while the hybrid strategy achieves the greatest reduction of 42% and maintains CO2 levels and thermal comfort within recommended limits. Although hybrid systems provide seasonal advantages, their complexity may limit applicability. In addition to technical analysis, this study also explores the financial and tax-related challenges associated with retrofitting ventilation systems in university buildings. Investment payback periods, operational costs, and potential tax incentives are discussed to evaluate economic viability. Overall, the endorse hybrid ventilation as the most cost-effective strategy where mixed-mode control is feasible, and DCV as a practical alternative for buildings unable to employ natural ventilation.