WoS
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14411/18
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Article Next Generation Mood Adaptive Behavioral Modeling for Decarbonizing Office Buildings and Optimizing Thermal Comfort(MDPI, 2026-04-08) Alkan, Nese; Turhan, Cihan; Doruk, Ozgur Resat; Ozbey, Mehmet Furkan; Thapa, Samar; Chen Austin, Miguel; Austin, Miguel Chen; Pekcan, PoyrazConventional Heating, Ventilation, and Air Conditioning (HVAC) control systems primarily rely on environmental and physiological parameters, largely ignoring the critical influence of psychological states on thermal comfort. Overlooking this factor often leads to suboptimal occupant satisfaction, energy inefficiency and thus carbon dioxide (CO2) emissions. To this aim, this study introduces a novel mood-adaptive HVAC control system integrating psychological feedback to decrease CO2 emissions in office buildings by reducing energy consumption and optimizing comfort. A total of 7000 thermal facial measurement records and high-resolution camera images were collected across seven mood state conditions using video stimuli and the Profile of Mood States (POMS) questionnaire to evaluate mood variations. A dual artificial intelligence system was developed: a Convolutional Neural Network (CNN) for analyzing facial expressions and an Artificial Neural Network (ANN) for processing facial temperatures via thermal imaging. These models collectively predict occupant mood in real-time, and a custom-designed wearable necklace interface transmits this data to dynamically adjust HVAC setpoints. To evaluate system performance, energy consumption was directly measured in real-life operations using an energy analyzer, without relying on simulations. Results indicate that this prototype personalized mood-driven system has the potential to enhance perceived thermal comfort while achieving up to a 20% reduction in carbon emissions compared to conventional systems. This human-centered approach significantly advances intelligent building management and climate change mitigation.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 Body Surface Area Indexing Attenuates Apparent Early eGFR Decline After Sleeve Gastrectomy: A Retrospective Cohort Study(MDPI, 2026-04-15) Karahisar Sirali, Semahat; Dede, Fatih; Banli, Oktay; Bayrakdar Çağlayan, Feyza; Demir, Mehmet Emin; Cankaya, Emre; Babaoglu, HakanBackground: Early postoperative changes in creatinine-based estimated glomerular filtration rate (eGFR) after bariatric surgery can be misread as a kidney injury. During rapid weight loss, indexing eGFR to a fixed body surface area (BSA) of 1.73 m(2) may alter apparent trajectories. We compared absolute (mL/min) and BSA-indexed (mL/min/1.73 m(2)) eGFR changes after sleeve gastrectomy, stratified by baseline glomerular hyperfiltration (GH). Methods: In this retrospective cohort of 145 adults undergoing laparoscopic sleeve gastrectomy, serum creatinine was obtained at baseline (<= 30 days pre-op) and 3 months (post-op days 75-105). Indexed eGFR was calculated with the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 creatinine equation; BSA with the Mosteller formula; and absolute eGFR as indexed eGFR & times; (BSA/1.73). GH was defined as indexed eGFR >= 120 mL/min/1.73 m(2). A REML mixed-effects model (Group, Time, Group & times; Time) with patient-cluster bootstrap inference was used. An age-adjusted sensitivity model including Age and Age & times; Time was also fitted. Results: Fifty-four participants (37%) met the GH criteria. Absolute eGFR declined by -26.6 mL/min in GH versus -17.3 mL/min in non-GH (difference-in-differences [DiD] -9.3 mL/min; 95% CI -13.9 to -4.7; p < 0.001). The indexed eGFR changes were smaller (-4.2 vs. -0.5 mL/min/1.73 m(2); DiD -3.7; 95% CI -7.3 to -0.03; p = 0.048; bootstrap p_sign = 0.052). In the age-adjusted sensitivity model, the Group & times; Time interaction for absolute eGFR attenuated but remained statistically significant (-6.57 mL/min; 95% CI, -13.09 to -0.06; p = 0.048), whereas the corresponding interaction for indexed eGFR was attenuated and no longer statistically significant (-3.99 mL/min/1.73 m(2); 95% CI -9.15 to 1.16; p = 0.129). Conclusions: Within three months after sleeve gastrectomy, participants with higher baseline indexed filtration showed a larger decline in absolute eGFR but only a small change in indexed eGFR. These results show that early postoperative creatinine-based eGFR trajectories are scale dependent and should be interpreted cautiously during rapid weight loss. Because postoperative acute kidney injury (AKI) was not adjudicated and direct kidney function markers were unavailable, this study does not distinguish physiological hemodynamic change from structural kidney injury. Reporting both absolute and indexed eGFR may improve early postoperative interpretation and help align dosing decisions with rapid changes in body size.Article Citation - WoS: 1Citation - Scopus: 1Balance, Gait and Foot Pressure Distribution in Neuropathic Pain Associated with Lumbar Disc Degeneration(MDPI, 2025-02-21) Yavuz, Ferdi; Korkusuz, Suleyman; Korkusuz, Busra Seckinogullari; Yuruk, Zeliha Ozlem; Kibar, SibelBackground: This study aimed to evaluate the effects of NP associated with LDD on balance, gait and foot pressure distribution. Methods: This prospective controlled study was conducted on 42 individuals aged between 40 and 70 years. There were 3 groups in the study: individuals diagnosed with NP associated with LDD (n = 14), individuals with LDD without NP (n = 14), and the control group (n = 14). The Force Plate system and Core Balance System measured static and dynamic postural balance and stability limits. Gait and dynamic plantar pressure distribution analyses were performed with a computerized gait evaluation system. Results: The Leeds Assessment of Neuropathic Signs and Symptoms (LANSS), VAS during gait, and Oswestry Disability Index (ODI) scores were higher in the LDD with NP group than in the LDD without NP group (p < 0.05). It was found that LDD with NP group had backward dynamic balance control (p < 0.05). There was no significant difference in balance control, dynamic plantar pressure distribution, and spatiotemporal gait parameters between the groups (p > 0.05). Conclusions: Although participants with NP had higher levels of pain severity in gait and disability, there was no difference in postural balance, dynamic plantar pressure distribution, and spatiotemporal gait parameters compared to participants with LDD without NP and healthy individuals. All participants with LDD were unilaterally affected. Therefore, postural balance and gait tasks would be able to compensate for the unaffected limb.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.Article Prognostic Value of the C-Reactive Protein-Albumin-Lymphocyte (CALLY) Index for 1-Year Mortality After Transcatheter Aortic Valve Implantation(MDPI, 2026-02-09) Guney, Murat Can; Suygun, Hakan; Turinay Ertop, Zeynep Seyma; Polat, Melike; Bozkurt, Engin; Ayhan, Huseyin; Keles, TelatObjectives: Systemic inflammation, malnutrition, and immune dysregulation have emerged as important determinants of long-term outcomes after transcatheter aortic valve implantation (TAVI). The C-reactive protein-albumin-lymphocyte (CALLY) index is a novel immunonutritional biomarker that integrates these pathophysiological domains; however, its prognostic value in TAVI patients has not yet been investigated. This study aimed to evaluate the association between the CALLY index and 1-year mortality after TAVI. Methods: This retrospective observational study included 532 consecutive patients who underwent TAVI at a tertiary-care center between 2014 and 2023. Baseline laboratory parameters were obtained before the procedure, and the CALLY index was calculated as (albumin & times; lymphocyte count)/(C-reactive protein & times; 10). The primary endpoint was 1-year mortality. Receiver operating characteristic (ROC) curve analysis was performed to assess the discriminative ability of the CALLY index and conventional surgical risk scores. Multivariable regression analyses were used to identify independent predictors of mortality. Results: During the 1-year follow-up period, 85 patients (15.9%) died. Patients who died had significantly lower baseline CALLY index values compared to survivors (p < 0.001). The CALLY index demonstrated good discriminative performance for 1-year mortality (AUC: 0.797), outperforming EuroSCORE II (AUC: 0.705) and the Society of Thoracic Surgeons (STS) score (AUC: 0.619). A CALLY cut-off value of 0.45, derived using Youden's index, was associated with a more than threefold increased risk of mortality. In multivariable analysis, the CALLY index remained independently associated with 1-year mortality, along with EuroSCORE II and more than mild mitral regurgitation. Conclusions: The CALLY index is a strong and independent predictor of 1-year mortality after TAVI and provides incremental prognostic value beyond conventional surgical risk scores. Given its simplicity and reliance on routinely available laboratory parameters, the CALLY index may serve as a practical tool for long-term risk stratification in patients undergoing TAVI.Article Algorithm-Driven Placement Optimization of Aircraft-Mounted VHF Antennas for Mutual Coupling Reduction(MDPI, 2026-03-12) Hakanoglu, Baris Gurcan; Dalveren, Yaser; Oz, Emre; Kara, Ali; Derawi, MohammadThis study investigates algorithm-driven placement optimization of two aircraft-mounted VHF monopole antennas to mitigate mutual coupling under realistic installation constraints. A parameterized 3D aircraft model inspired by general-aviation platforms is analyzed using full-wave electromagnetic simulations over the 30-100 MHz band. The optimization problem is formulated to reduce inter-antenna coupling across the operating band while restricting the search space to physically installable regions on the airframe. Two global optimization methods, Genetic Algorithm and Particle Swarm Optimization, are applied and compared under the identical constraints and objective definitions. The results show that both optimizers achieve a significant reduction in coupling relative to non-optimized placements, with comparable overall performance. Installed far-field radiation characteristics are further evaluated to verify that the optimized solutions preserve, and in some cases improve, the omnidirectional coverage required for airborne VHF communication. The proposed workflow provides a practical, simulation-driven framework for electromagnetic compatibility (EMC)-oriented antenna integration on complex aircraft platforms.Article A Proportional Hazards Mixture Cure Model for Subgroup Analysis: Inferential Method and an Application to Colon Cancer Data(MDPI, 2025-12-24) Liu, Kai; Balakrishnan, Narayanaswamy; Peng, YingweiWhen determining subgroups with heterogeneous treatment effects in cancer clinical trials, the threshold of a variable that defines subgroups is often pre-determined by physicians based on their experience, and the optimality of the threshold is not well studied, particularly when the mixture cure rate model is considered. We propose a mixture cure model that allows optimal subgroups to be estimated for both the time to event for uncured subjects and the cure status. We develop a smoothed maximum likelihood method for the estimation of model parameters. An extensive simulation study shows that the proposed smoothed maximum likelihood method provides accurate estimates. Finally, the proposed mixture cure model is applied to a colon cancer study to evaluate the potential differences in the treatment effect of levamisole plus fluorouracil therapy versus levamisole alone therapy between younger and older patients. The model suggests that the difference in the treatment effect on the time to cancer recurrence for uncured patients is significant between patients younger than 67 and patients older than 67, and the younger patient group benefits more from the combined therapy than the older patient group.Article Effect of Aluminizing on the Oxidation of Inconel 718 and Inconel 738LC Superalloys at 925-1050 °C(MDPI, 2025-12-16) Telbakiroglu, Yusuf Burak; Konca, ErkanThis study was undertaken to investigate the effect of aluminizing on the oxidation of Inconel 718 and Inconel 738LC superalloys. Bare and high-activity chemical vapor deposition (CVD) aluminized Inconel 718 and Inconel 738LC samples were oxidized in air at 925, 1000, and 1050 degrees C for 200 h. Detailed cross-sectional examinations, elemental analyses, mass change measurements, and X-ray diffraction studies were performed. It was observed that the oxidation resistances of both alloys were significantly improved by the Al2O3 scale formed on the NiAl layer that was created on the surfaces of the samples during aluminizing. The beneficial effect of aluminizing was found to be more evident in the case of Inconel 738LC alloy samples which showed lower oxidation rates at all test temperatures. The results have been discussed on the basis of the differences in aluminum contents of the alloys and their effects on diffusion.Article Citation - WoS: 1Citation - Scopus: 1Experimental Investigation of Energy Efficiency, SOC Estimation, and Real-Time Speed Control of a 2.2 kW BLDC Motor with Planetary Gearbox under Variable Load Conditions(MDPI, 2025-12-21) Abouseda, Ayman Ibrahim; Doruk, Resat; Emin, Ali; Lopez-Guede, Jose ManuelThis study presents a comprehensive experimental investigation of a 2.2 kW brushless DC (BLDC) motor integrated with a three-shaft planetary gearbox, focusing on overall energy efficiency, battery state of charge (SOC) estimation, and real-time speed control under variable load conditions. In the first stage, the gearbox transmission ratio was experimentally verified to establish the kinematic relationship between the BLDC motor and the eddy current dynamometer shafts. In the second stage, the motor was operated in open loop mode at fixed reference speeds while variable load torques ranging from 1 to 7 N.m were applied using an AVL dynamometer. Electrical voltage, current, and rotational speed were measured in real time through precision transducers and a data acquisition interface, enabling computation of overall efficiency and SOC via the Coulomb counting method. The open loop results demonstrated that maximum efficiency occurred in the intermediate-to-high-speed region (2000 to 2800 rpm) and at higher load torques (5 to 7 N.m) while locking the third gearbox shaft produced negligible parasitic losses. In the third stage, a proportional-integral-derivative (PID) controller was implemented in closed loop configuration to regulate motor speed under the same variable load scenarios. The closed loop operation improved the overall efficiency by approximately 8-20 percentage points within the effective operating range of 1600-2500 rpm, reduced speed droop, and ensured precise tracking with minimal overshoot and steady-state error. The proposed methodology provides an integrated experimental framework for evaluating the dynamic performance, energy efficiency, and battery utilization of BLDC motor planetary gearbox systems, offering valuable insights for electric vehicle and hybrid electric vehicle (HEV) drive applications.
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