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Article Citation - WoS: 25Citation - Scopus: 26Identifying the Potentials for Charge Transport Layers Free N-P Homojunction-Based Perovskite Solar Cells(Pergamon-elsevier Science Ltd, 2022) Khan, Danish; Sajid, Sajid; Khan, Suliman; Park, Jongee; Ullah, IhsanPerovskite solar cells (PSCs) with no charge transport layers (CTLs) could be one of the major device architectures for the production of simple and low-cost devices. However, CTLs-free PSCs based on n-p homojunction have yet to show high power conversion efficiency (PCE), which is most likely due to inadequate light-and charge-management in the p-type perovskite. The device operation is examined using Solar Cell Capacitance Simulator (SCAPS)-software, and a novel n-p homojunction design is proposed to attempt efficient CTLs-free PSCs. Several aspects of p-type layer that can affect device performance, such as acceptor density, photon harvesting capability, defects density, and resistances to the transport of charge-carriers are scrutinized and adjusted. Furthermore, the effects of different work-functions of metal electrodes are examined. A suitable acceptor concentration is required for oriented charge transport. It is determined that a p-type perovskite with a thickness of 0.3 mu m is advantageous for high performance. A metal electrode with a high work-function is essential for efficient device. Consequently, a PCE of 15.60% is obtained with an optimal defect density of E15 cm(-3), indicating that n-p homojunction-based CTLs-free PSCs are promising since they simplify the device design and fabrication process while retaining an acceptable PCE.Article Citation - WoS: 12Citation - Scopus: 15Discrete Parameter-Nonlinear Constrained Optimisation of a Gear Train Using Genetic Algorithms(inderscience Enterprises Ltd, 2005) Dolen, M.; Kaplan, H.; Seireg, A.This paper investigates the optimal design of a four-stage gear train using genetic algorithms. Five different genetic encoding schemes, which incorporate various heuristic search techniques, are proposed to deal with the most critical constraints of the problem. The fitness criterion used by all genetic algorithms includes a merit function for minimising the size of the gearbox. The results show improvement in the design merit over previous approaches without reliance on the designer's interaction to avoid geometric constraint violations and facilitate the convergence.Article Citation - WoS: 10Citation - Scopus: 11Dispersive Optical Constants of Thermally Deposited Agin5s8< Thin Films(Elsevier Science Sa, 2008) Qasrawi, A. F.Agln(5)S(8) thin films were obtained by the thermal evaporation of Agln(5)S(8) crystals onto ultrasonically cleaned glass substrates. The films are found to exhibit polycrystalline cubic structure. The calculated lattice parameter of the unit cell (a) is 10.78 angstrom. The transmittance data of the as grown films which was recorded at 300 K in the incidence wavelength (lambda) range of 320-1000 nm are used to calculate the refractive, n(lambda). The transmittance and reflectance data are also used to calculate the absorption coefficient of the as grown Agln5S8 thin films. The fundamental absorption edge is found to be corresponding to a direct allowed transitions energy band gap. This band-to-band transition energy is found to be 1.78 eV and it is consistent with that reported for Agln(5)S(8) single crystals. (c) 2007 Elsevier B.V. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 14Existence of a Solution of Integral Equations Via Fixed Point Theorem(Springeropen, 2013) Gulyaz, Selma; Karapinar, Erdal; Rakocevic, Vladimir; Salimi, PeymanIn this paper, we establish a solution to the following integral equation: u(t) = integral(T)(0) G(t, s)f(s, u(s)) ds for all t is an element of [0,T], (1) where T > 0, f : [0, T] x R -> R and G : [0, T] x [0, T] -> [0, infinity) are continuous functions. For this purpose, we also obtain some auxiliary fixed point results which generalize, improve and unify some fixed point theorems in the literature.Article Analysing the Views of School of Foreignlanguages Instructors About Organizationalculture(Ani Publishing, 2021) Akman, Devrim; Koşar, DidemThis study aims to investigate the views of school of foreignlanguages instructors about organizational culture. The study is designed inqualitative research method and as a case study. The study was conductedwith 15 school of foreign languages instructors who were selected bymaximum variation sampling method during the 2018 and 2019 academicyear in Ankara. Semi structured interviews were conducted to gather dataand content analysis was used to analyse the data. The study emphasisesthat for the powerful school culture, instructors should focus on orientation,social activities, merit, and democratic management style.Article Citation - WoS: 62Citation - Scopus: 70Kinetic Studies on the Multi-Enzyme Solution Produced Via Solid State Fermentation of Waste Bread by aspergillus Awamori(Elsevier Science Bv, 2013) Melikoglu, Mehmet; Lin, Carol Sze Ki; Webb, ColinThe aim of this study was kinetic analysis of the multi-enzyme solution produced from waste bread via solid state fermentation by Aspergillus awamori. It was found that at normal temperature for hydrolysis reactions, 60 degrees C, the activation energies for denaturation of A. awamori glucoamylase, 176.2 kJ/mol, and protease, 149.9 kJ/mol, are much higher than those for catalysis of bread starch, 46.3 kJ/mol, and protein, 36.8 kJ/mol. Kinetic studies showed that glucoamylase and protease in the multi-enzyme solution should have at least two conformations under the two temperature ranges: 30-55 degrees C and 60-70 degrees C. Thermodynamic analysis showed that, deactivation of glucoamylase and protease in the multi-enzyme solution can be reversible between 30 degrees C and 55 degrees C, since Delta S is negative and Delta H is positive. On the other hand, for glucoamylase and protease, both Delta S and Delta H are positive between 60 degrees C and 70 degrees C. This means that the deactivation of both enzymes in the multi-enzyme solution is spontaneous in this temperature range. It was also found that the glucoamylase produced in the solid state fermentation of waste bread is more thermally stable than the protease in the mixture. Consequently, the protease had little or no effect on the stability of the glucoamylase. Furthermore, the half-life of the glucoamylase produced from waste bread pieces was much higher than that produced from wheat flour. This is an important finding because the mode of production, via solid state fermentation, appears to have increased the thermostability of the enzyme significantly. (C) 2013 Elsevier B.V. All rights reserved.Article Citation - WoS: 8Citation - Scopus: 11Proposing a novel mixed-reality framework for basic design and its hybrid evaluation using linkography and interviews(Springer, 2022) Cindioglu, Hasane Ceren; Gursel Dino, Ipek; Surer, ElifImmersive Virtual Environments (IVEs), particularly Mixed-Reality (MR) technologies, continue to have an increasing impact on design processes and design education. This study focuses on MR's potentials in Basic Design (BD) education and its influence on novice designers' design thinking abilities. In this study, through a newly developed MR-based design framework, DesignMR, a comparative analysis between design processes in MR and the physical environment is presented. A hybrid evaluation methodology is used in the context of three-dimensional (3D) BD tasks through two sets of protocol studies: Linkography and exit interviews. Linkography is a method to analyze the design process based on detecting design moves and their links with each other. In this study, linkographic analyses point to an increase in critical moves and link index values in MR as compared to the physical environment for all participants. This indicates that MR can trigger improved creativity, design productivity, and design exploration by idea generation. Exit interviews highlighted the positive impact of DesignMR on the motivation, work efficiency, and 3D perception of the participants. Further research will be pursued for improved hand gestures to increase the effectiveness of object interaction.Article Citation - WoS: 3Citation - Scopus: 3How Do Implant Threads and Diameters Affect the All-On Success? a 3d Finite Element Analysis Study(IOS Press BV, 2022) Zor,Z.F.; Klllnç,Y.; Erkmen,E.; Kurt,A.; Kilinc, YelizBACKGROUND: The effect of different thread designs and diameters on the all-on-four concept is unclear. OBJECTIVE: The aim of the study was to clarify the differences in stress distribution of dental implants with various thread designs and diameters based on the all-on-four concept with three dimensional (3D) finite element analysis (FEA). METHODS: A 3D model of a totally edentulous mandible was used to perform the FEA. Four different models (M1, M2, M3, and M4) including 3.5 and 4.3 mm diameter dental implants with active and passive threaded designs were generated. The dental implants were positioned according to the all-on-four concept. The Von Mises stresses on dental implants and maximum and minimum principal stresses (Pmax and Pmin) on bony structures were calculated under vertical, oblique and horizontal loads. RESULTS: For Von Mises stresses, the highest stress values were detected on the distal implants for all models. Distal implants had also the highest stress values for vertical loading. The Von Mises stresses were found to be concentrated around the implant's neck. In all models the highest Pmax and Pmin stresses occurred in the bone surrounding the distal implant. It was noted that the active threaded implants showed the highest Pmax and Pmin stress values. CONCLUSION: The implant thread design and diameter might have a strong influence on the stress values in the all-on-four concept. © 2022 - IOS Press. All rights reserved.Article Bacterial Profiling of Brined Grapevine Leaves Collected From Different Local Markets in Türkiye(John Wiley and Sons Inc, 2025) Ucak, S.; Yegin, Z.; Yurt, M.N.Z.; Sudagidan, M.; Altunbas, O.; Ozalp, V.C.Microorganisms linked to the grapevine, Vitis vinifera, can impact crop quality, plant growth, and human and plant health. This study examined the bacterial community structures of brined grapevine leaves (n = 56) taken from seven distinct regions in Türkiye using next-generation sequencing technology. Investigations were also conducted into the samples' chemical properties. Firmicutes was the dominant phylum, followed by Proteobacteria, Actinobacteria, and Bacteroidetes. Bacillaceae was the predominant family in the analyzed samples, followed by Clostridiaceae, Peptostreptococcaceae, and Enterobacteriaceae. Bacillus was the dominant genus, followed by Lysinibacillus and Clostridium sensu stricto. The samples exhibited differences in terms of pH, total acidity, and salt content. The pH values of the brined grapevine leaves ranged from 2.31 to 6.91, the acidity levels ranged from 0.09% to 1.80%, and the salt percentages ranged from 3.39% to 49.14%. This research provides pioneering information for bacterial community analysis of brined grapevine leaves. © 2025 Wiley-VHCA AG, Zurich, Switzerland.Article The Effect of Endurance-Based Sports on Athlete Success and Psychological Well-Being(Campus Educa Sports Sl, 2025) Ozpinar, Saliha; Yucel, Ali Serdar; Korkmaz, Murat; Oztas, Dilek; Kuyucu, Mihalis Michael; Aras, Goksen; Yüce, Ali SerdarThe aim of this study is to examine the effects of psychological resilience on sport success and mental health. The relationships between commitment, control and challenge, which are sub-dimensions of psychological resilience, and sport success and psychological wellbeing were evaluated and discussed in detail. Today, the problems arising due to the increasing competitive environment and stress factors have made it more important for athletes to be psychologically strong. Although the relationship between psychological resilience and sport success has been previously examined in the literature, studies evaluating the individual effects of the sub-dimensions of resilience in a large sample group are quite limited. This study aims to overcome this deficiency and make an up-to-date contribution to the subject. A total of 684 students (72 percent male, 28 percent female) studying at the Faculties of Sport Sciences of 16 universities in Istanbul, Ankara, Izmir, Bursa and Antalya participated in the study. Participants completed the Resilience Scale and Mental Health Inventory, and their sporting achievements were evaluated by their coaches using the Sport Achievement Scale. Data were collected via Google Forms (R) and analysed using SPSS 22.0 software with correlation, regression and Granger causality tests. The findings revealed that all resilience sub-dimensions showed positive and significant relationships with sport achievement ( R-2=0.93) and psychological well-being (R-2=0.68). Especially control and challenge factors had the strongest effects. As a result of the research, commitment, control and challenge, which are the sub-dimensions of psychological resilience, significantly affect both success levels and psychological well-being of athletes. Therefore, resilience development programmes for athletes should focus on these areas.
