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Article Citation - WoS: 11Citation - Scopus: 11Experimental and Modeling Studies of a High-Temperature Electrochemical Hydrogen Compressor(Pergamon-elsevier Science Ltd, 2024) Durmus, Gizem Nur Bulanik; Kuzu, Cemil; Devrim, Yilser; Colpan, C. Ozgur; Bulanık Durmuş, Gizem NurSome non-technical factors such as economics and logistics prevent hydrogen (H2) tech-nologies from becoming more widespread in daily life. Today, the prevalence of H2 tech-nologies requires new technological developments. Electrochemical hydrogen compressors (ECHC) are of great interest due to their ability to pressurize and purify in one step. In this study, the electrochemical H2 compression performance of high phosphoric acid (PA) doped poly 2,2-m-phenylene-5,5-benzimidazole (PBI) membrane-based HT-ECHC under high temperature and non-humid conditions was investigated through both an experimental and a numerical approach. The H2 compression capacity of HT-ECHC at different operating voltages was examined by performance tests at 160 degrees C, and it was determined that the electrochemical compression performance increased with increasing operating voltage. It was observed that the current density values also increased with increasing voltage, and it was determined that a current density of 61.2 A was obtained at 1 V. As a result of the tests, H2 was successfully compressed from atmospheric pressure to 60 bar by HT-ECHC without any gas leakage. The results of the developed model were compared with the experimental performance test data, and the variation of molar flow, cell voltage, and cell efficiency over time was examined. It has been determined that the back diffusion from the cathode to the anode in the cell increases with the increasing operating voltage of HT-ECHC and therefore the cell efficiency decreases. It has been evaluated that the developed model and experimental results are in good agreement. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Article Role of Latissimus Dorsi-Thoracolumbar Fascia Complex Stretching on Pain and Pain-Related Parameters in Patients With Chronic Low Back Pain: A Randomised Clinical Trial(Wiley, 2025) Ulug, Naime; Kodak, Seyde Busra; Kodak, Muhammed Ihsan; Aslan, Sema NurBackground Fascial stretching is gaining interest as a potential intervention for pain management. However, evidence regarding the effect of latissimus dorsi-thoracolumbar fascia (LD-TLF) complex stretching in patients with chronic low back pain (CLBP) remains limited. Therefore, this study aimed to investigate the effects of LD-TLF complex stretching on pain-related factors and disability in patients with CLBP. Methods Thirty patients with CLBP were randomly assigned to a study group (n = 15; 7 men, 8 women) and a control group (n = 15; 7 men, 8 women). The study group received 4 weeks of LD-TLF complex stretching in combination with conventional physiotherapy, while the control group received conventional physiotherapy only. Outcomes were assessed before and after the interventions, including primary measures of pain pressure thresholds (PPT) at thoracolumbar fascia levels (L1, L3 and 12th costa), and secondary measures included the Pain Sensitivity Questionnaire (PSQ), the effects of pain on daily activities measured by the Brief Pain Inventory (BPI), and disability assessed by the Oswestry Disability Questionnaire (ODQ). Results Pre- and post-treatment PPTs, at the L1, L3 vertebrae and 12th costa levels, demonstrated significant differences between the study group and control groups. Post-treatment thresholds were significantly higher compared to pre-treatment thresholds (p < 0.001, eta p(2) = 0.67; p < 0.001, eta p(2) = 0.61; p < 0.001, eta p(2) = 0.74). Additionally, significant improvements were found in PSC, BPI and ODQ scores in the study group compared to the control group (p < 0.05). Conclusion The results of this study suggest that stretching the LD-TLF complex may be a beneficial addition to the conventional physiotherapy approach for patients with CLBP. Specifically, LD-TLF complex stretching, when used in combination with conventional physiotherapy, appears to provide improved pain thresholds, decreased pain sensitivity and pain during activity, as well as reduced disability compared to conventional physiotherapy alone in patients with CLBP.Article Health Beliefs and Attitudes: a Comparison Between Turkey and Palestine(Routledge Journals, Taylor & Francis Ltd, 2018) Menawi, Wafaa Allam; Tengilimoglu, Dilaver; Dziegielewski, Sophia F.The purpose of this study is to identify the beliefs and attitudes that influence health-related behavior while comparing two countries that can have different political and economic structures. This study also gathers both Turkish and Palestinian citizens' beliefs and attitudes towards health determinants. To assess and compare citizens' attitudes toward health care and health determinants a total of 4,100 questionnaires were distributed, whereas 2,600 were distributed in Turkey, and another 1,500 questionnaires in the Palestine. According to the research, the individuals surveyed in Turkey noted that smoking, stress, and getting access to a medical institution were noted as the most influential determinants which affect their health; whereas, the people of Palestine thought that income status, and educational levels were the most influential factors in health. In addition, it was found that there were some statistically significant differences between participants' responses in Turkey and Palestine; however, what both samples shared was that economic factors were an important factor affecting health beliefs and attitudes, regardless of where a participant lived. Finally, comparisons and future recommendations are made to improve health-related beliefs, attitudes and behaviors in both countries.Conference Object Citation - Scopus: 4Comparison of computer-based propagation models with experimental data collected in an urban area at 1800 MHz(Institute of Electrical and Electronics Engineers Inc., 2015) Acar,T.; Caliskan,F.; Aydin,E.Nowadays a lot of models are set for the efficient and economic usage of frequency band since the band is a limited source. Therefore, the propagation models created for this purpose were studied in the literature. These models are Free Space Path Loss (Fspl) + Reflection plus Multiple Diffraction (RMD), COST-Hata and COST-WI models. In order to compare the success of the models, electric field strength measurements were taken in a chosen district (Mustafa Kemal Mahallesi - Ankara, Turkey) where an irregular structure style can be observed. First set of measurements were recorded at random coordinates and second set of measurements were collected by the following coordinates tracking on a single line. As a conclusion, measured values were compared with the results which were taken from the mentioned models with graphical presentations. The most appropriate model was tried to be found and as another aim of the study, a correction factor was generated as a modification for COST-Hata propagation model. © 2015 IEEE.Article Citation - WoS: 13Citation - Scopus: 17Effect of hydrogen on fracture locus of Fe-16Mn-0.6C-2.15Al TWIP steel(Pergamon-elsevier Science Ltd, 2020) Bal, Burak; Cetin, Baris; Bayram, Ferdi Caner; Billur, ErenEffect of hydrogen on the mechanical response and fracture locus of commercial TWIP steel was investigated comprehensively by tensile testing TWIP steel samples at room temperature and quasi-static regime. 5 different sample geometries were utilized to ensure different specific stress states and a digital image correlation (DIC) system was used during tensile tests. Electrochemical charging method was utilized for hydrogen charging and microstructural characterizations were carried out by scanning electron microscope. Stress triaxiality factors were calculated throughout the plastic deformation via finite element analysis (FEA) based simulations and average values were calculated at the most critical node. A specific Python script was developed to determine the equivalent fracture strain. Based on the experimental and numerical results, the relation between the equivalent fracture strain and stress triaxiality was determined and the effect of hydrogen on the corresponding fracture locus was quantified. The deterioration in the mechanical response due to hydrogen was observed regardless of the sample geometry and hydrogen changed the fracture mode from ductile to brittle. Moreover, hydrogen affected the fracture locus of TWIP steel by lowering the equivalent failure strains at given stress triaxiality levels. In this study, a modified Johnson-Cook failure mode was proposed and effect of hydrogen on damage constants were quantified. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Article Citation - WoS: 2Citation - Scopus: 2Performance of Ge-Sandwiched Gase Layers(Springer, 2018) Qasrawi, A. F.; Qasrawı, Atef Fayez Hasan; Abdallah, Maisam M. A.; Qasrawı, Atef Fayez Hasan; Department of Electrical & Electronics Engineering; Department of Electrical & Electronics EngineeringIn the current work, we report the effect of sandwiching Ge between two stacked layers of GaSe. The GaSe and Ge-sandwiched GaSe were subjected to x-ray diffraction, optical spectrophotometry and impedance spectroscopy measurement and analysis. The presence of a Ge layer between two layers of GaSe was observed to cause uniform deformation and increase the absorption of light by GaSe. The response of the dielectric constant to incident light was also significantly enhanced by Ge sandwiching. In addition, Drude-Lorentz modeling of the imaginary part of the dielectric constant revealed that the layer of Ge layer between GaSe layers increased the drift mobility from 30.76 cm(2)/Vs to 52.49 cm(2)/Vs. It also enhanced the plasmon frequency without altering the free carrier density. Moreover, Ge improved the band filtering features of GaSe. In particular, it enhanced the sensitivity of the impedance response to the incident signal and increased the return loss factor of GaSe when it was used as a high band pass filter.Article Citation - WoS: 28Citation - Scopus: 29Polycrystalline Diamond End Mill Cutting Edge Design To Improve Ductile-Mode Machining of Silicon(Elsevier Science inc, 2018) Oliaei, S. N. B.; Karpat, Y.Silicon is a commonly used material in optoelectronics and micro fluidics devices. Micro mechanical milling of silicon with polycrystalline diamond (PCD) tools has the potential to produce three-dimensional surfaces with good surface finish and an increased material removal rate. PCD micro end mill geometry is known to influence process outputs yet its effect has not been studied in detail. In this study, a PCD end mill with a hexagonal geometry has been considered, and its micro cutting geometry has been modified to have a parallelogram shape featuring a large negative rake angle on the bottom of the tool. The proposed micro geometry also reduces the contact area between the tool and the work material. The proposed geometry was fabricated using wire electric discharge machining (WEDM). Ductile-to-brittle transition conditions and areal surface roughness have been investigated as a function of tool geometry and feed during micro milling of silicon. A significant improvement in material removal rate and surface roughness has been obtained compared to a commercially available PCD end mill having hexagonal geometry with flat bottom. The results show that PCD micro end mill geometry significantly affects the process outputs.Article An Investigation Into The AI-Assisted Visualization Of Children’s Songs: The Case Of Ali Baba’s Farm(Nilgun SAZAK, 2025) Südor, S.; İpekçiler, B.This study aims to visualize children’s songs, which are part of primary-level music education, using AI-supported tools. The objectives of the Ministry of National Education’s music course curriculum were examined, and both the themes to be emphasized in song selection and the pedagogical functions of children’s songs were analyzed. In the literature review, the Web of Science and Google Scholar databases were used. The obtained source data were analyzed with the VOSviewer software to generate conceptual maps, through which thematic trends in the field were identified. In the practical part of the study, the children’s song “Old MacDonald’s Farm” was visualized in detail using two different AI-supported tools: RunwayML and WZRD.ai. In RunwayML, prompt-based scenes were generated using the “text-to-video” feature, and visuals compatible with the lyrics of the song were created. On the WZRD.ai platform, visuals were automatically generated in response to sound waves, and the limitations of the platform were examined. Based on the findings, it was concluded that RunwayML offers more effective results for pedagogical content production, while WZRD. ai, despite its technical capabilities, falls short in delivering child-appropriate visual stimuli. The study also provides a theoretical foundation on synesthesia and discusses how AI tools can be integrated into music education in early childhood and primary school levels. The findings indicate that AI-supported visualization tools have the potential to provide engaging and flexible educational materials that support learning at the primary school level. It is recommended that teacher training programs develop hands-on modules for these tools, and that future research focus on how these technologies can be adapted to various songs, age groups, and learning domains. © © 2025 The Author(s). This is an open access article distributed under the Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium or format, provided the original work is properly cited.Article Citation - Scopus: 1Patient Safety in Healthcare: A Proposal for Ensuring the Use of Regulation-Compliant Safety Devices(Springer Heidelberg, 2025) Bayrak, TuncayMedical devices used in health care should fulfill the requirements of the technical regulations to protect patient health. Difficulties in enforcing stricter rules in the new medical device regulations may negatively affect the continuity of care. This study examines the status of manufacturers' compliance with medical device regulations, based on predefined criteria, and proposes a collaborative action plan and an approach to verify regulatory compliance. We conducted a nationwide survey comprising questions grouped by criteria to understand the status of the manufacturers in terms of compliance with the Medical Device Regulation. Four hundred sixty-seven manufacturers participated in the survey. We achieved a Cronbach's alpha of 0.77, which indicates that the survey is statistically reliable. We applied the independent samples t-test to the responses to determine significant features per question and employed factor analysis to investigate the relationships of the questions. The results of independent samples t-tests showed statistically significant differences across groups in replies to several survey items (p < 0.05), indicating that participants' opinions varied based on their demographic characteristics. We applied Exploratory Factor Analysis to introduce the relationships between the questions. The analysis revealed that manufacturers continue to face substantial challenges in acquiring sufficient knowledge and operational capability to meet MDR requirements. In light of these findings, we focused on the person responsible for regulatory compliance, who plays a central role in maintaining regulatory compliance within manufacturing organizations. We proposed an action plan at the macro level to introduce more effective action plans in cooperation with other stakeholders, including healthcare providers, and a verification approach for regulatory compliance to enhance the Person Responsible for Regulatory Compliance's competence. Manufacturers should implement effective postmarketing clinical follow-up plans involving device-oriented parameters for monitoring in the healthcare system, especially in collaboration with health professionals.Article Citation - WoS: 57Citation - Scopus: 66Development of 500 W Pem Fuel Cell Stack for Portable Power Generators(Pergamon-elsevier Science Ltd, 2015) Devrim, Yilser; Devrim, Huseyin; Eroglu, InciPolymer Electrolyte Membrane Fuel Cell (PEMFC) portable power generators are gaining importance in emergency applications. In this study, an air-cooled PEMFC stack was designed and fabricated for net 500 W power output. Gas Diffusion Electrodes (GDE's) were manufactured by ultrasonic spray coating technique. Stack design was based on electrochemical data obtained at 0.60 V was 0.5 A/cm(2) from performance tests of a single cell having the same membrane electrode assemblies (MEA) that had an active area of 100 cm(2). Graphite bipolar plates were designed and machined by serpentines type flow. The stack comprising of 24 cells was assembled with external fixing plates. The stack temperature was effectively regulated by the cooling fan based on on-off control system. A maximum power of 647 W was obtained from the stack. The PEMFC stack was stable during start-up and shutdown cycling testing for 7 days at 65 degrees C in H-2/air at a constant cell voltage. Copyright (c) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
