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Conference Object Citation - WoS: 7Citation - Scopus: 7Effect of Hardening Models on Different Ductile Fracture Criteria in Sheet Metal Forming(Springer France, 2016) Dizaji, Shahram Abbasnejad; Darendeliler, Haluk; Kaftanoglu, BilginPrediction of the fracture is one of the challenging issues which gains attention in sheet metal forming as numerical analyses are being extensively used to simulate the process. To have better results in predicting the sheet metal fracture, appropriate ductile fracture criterion (DFC), yield criterion and hardening rule should be chosen. In this study, the effects of different hardening models namely isotropic, kinematic and combined hardening rules on the various uncoupled ductile fracture criteria are investigated using experimental and numerical methods. Five different ductile fracture criteria are implemented to a finite element code by the user subroutines. The criterion constants of DFCs are obtained by the related experimental tests. The in-plane principle strains obtained by the finite element analyses for different DFCs are compared with the experimental results. Also, the experimental results are used to evaluate the principle strain values calculated by the finite element analysis for different combinations of DFCs and hardening rules. It is shown that some DFCs give better predictions if the appropriate hardening model is employed.Article Citation - WoS: 5Citation - Scopus: 5Development and Psychometric Analysis of a Pediatric Oncology Nurses' Educational Needs Scale(Wiley, 2023) Kudubes, Asli Akdeniz; Semerci, Remziye; Ozbay, Sevil Cinar; Ay, Ayse; Boztepe, HandanBackground/objectivesIt is important to determine the educational needs of pediatric oncology nurses in order to maximize and implement nursing care interventions. Therefore, this study aims to develop a valid and reliable measurement tool to determine pediatric oncology nurses' educational needs and examine its psychometric properties. Design/methodsThis methodological study was conducted with 215 pediatric oncology nurses in Turkey between December 2021 and July 2022. Data were collected with the "Nurse Information Form" and "Pediatric Oncology Nurses' Educational Needs Scale." IBM SPSS 21.0 and IBM AMOS 25.0 software programs were used for data analysis, and descriptive statistics were used to analyze numeric variables. Exploration and confirmatory factor analyses were performed to determine the scale's factorial structure. ResultsThe factorial analysis was used to test the structural validity of the scale. A five-factor structure consisting of 42 items was developed. The Cronbach's alpha coefficient for "Illness" was .978, "Chemotherapy and Side Effect" was .978, "Another Therapy and Side Effect" was .974, "Palliative Care" was .967, "Supportive Care" was .985, and the total score was .990. Fit indices resulting from the study were chi(2)/SD: 3.961, root mean square error of approximation (RMSEA): 0.072, goodness-of-fit index (GFI): 0.95, comparative-of-fit index (CFI): 0.96, and normed fit index (NFI): 0.95. ConclusionThe Pediatric Oncology Nurses' Educational Needs Scale is a valid and reliable scale for pediatric oncology nurses to determine their educational needs.Article Citation - WoS: 14Citation - Scopus: 14Analysis of Temperature-Dependent Forward and Leakage Conduction Mechanisms in Organic Thin Film Heterojunction Diode With Fluorine-Based Pcbm Blend(Springer, 2020) Yildiz, D. E.; Gullu, H. H.; Toppare, L.; Cirpan, A.The forward and reversed biased current-voltage behaviors of the organic diode were detailed in a wide range of temperatures. In this diode, a donor-acceptor-conjugated copolymer system was constructed with poly((9,9-dioctylfluorene)-2,7-diyl-(2-dodecyl-benzo[1,2,3]triazole)) as a partner of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). Two-order of magnitude rectification ratio was achieved, and the temperature-dependent values of saturation current, zero-bias barrier height, and ideality factor were extracted according to the thermionic emission model. The temperature responses of these diode parameters showed an existence of inhomogeneity in the barrier height formation. As a result, the observed non-ideal behavior was explained by Gaussian distribution of barrier height where low-barrier regions are effective in the forward biased conduction mechanism at low temperatures. Together with this analysis, series resistances were evaluated using Cheung's functions and also density of interface states were investigated. On the other hand, reverse biased current flow was found under the dominant effect of Poole-Frenkel effects associated with these interfacial traps. The reverse current conduction mechanism was detailed by calculating characteristic field-lowering coefficients and barrier height values in the emission process from the trapped state in the range of temperatures of interest.Article Citation - WoS: 11Citation - Scopus: 12A New Mixed Δ-Shock Model With a Change in Shock Distribution(Springer, 2023) Chadjiconstantinidis, Stathis; Tuncel, Altan; Eryilmaz, SerkanIn this paper, reliability properties of a system that is subject to a sequence of shocks are investigated under a particular new change point model. According to the model, a change in the distribution of the shock magnitudes occurs upon the occurrence of a shock that is above a certain critical level. The system fails when the time between successive shocks is less than a given threshold, or the magnitude of a single shock is above a critical threshold. The survival function of the system is studied under both cases when the times between shocks follow discrete distribution and when the times between shocks follow continuous distribution. Matrix-based expressions are obtained for matrix-geometric discrete intershock times and for matrix-exponential continuous intershock times, as well.Article Citation - WoS: 1Citation - Scopus: 1Solving an initial boundary value problem on the semiinfinite interval(Tubitak Scientific & Technological Research Council Turkey, 2016) Atalan, Ferihe; Guseinov, Gusein Sh.We explore the sign properties of eigenvalues and the basis properties of eigenvectors for a special quadratic matrix polynomial and use the results obtained to solve the corresponding linear system of differential equations on the half line subject to an initial condition at t = 0 and a condition at t = infinity.Article Citation - WoS: 1Citation - Scopus: 3Gamified Text Testing for Sustainable Fairness(Mdpi, 2023) Takan, Savas; Ergun, Duygu; Katipoglu, GoekmenAI fairness is an essential topic as regards its topical and social-societal implications. However, there are many challenges posed by automating AI fairness. Based on the challenges around automating fairness in texts, our study aims to create a new fairness testing paradigm that can gather disparate proposals on fairness on a single platform, test them, and develop the most effective method, thereby contributing to the general orientation on fairness. To ensure and sustain mass participation in solving the fairness problem, gamification elements are used to mobilize individuals' motivation. In this framework, gamification in the design allows participants to see their progress and compare it with other players. It uses extrinsic motivation elements, i.e., rewarding participants by publicizing their achievements to the masses. The validity of the design is demonstrated through the example scenario. Our design represents a platform for the development of practices on fairness and can be instrumental in making contributions to this issue sustainable. We plan to further realize a plot application of this structure designed with the gamification method in future studies.Article Citation - WoS: 3Evaluation of the Effects of Avatar on Learning Temporomandibular Joint in a Metaverse-Based Training(Wiley, 2024) Basmaci, Fulya; Bulut, Ali Can; Ozcelik, Erol; Ekici, Saliha Zerdali; Kilicarslan, Mehmet Ali; Cagiltay, Nergiz ErcilPurposeAvatars, representing users in the digital world, can influence users' behavior and attitudes. This study evaluates the impact of representing dental students receiving temporomandibular joint (TMJ) education in the metaverse via an anonymous or identified avatar.MethodsParticipants included 80 dental students in their fourth and fifth years of study. They were randomly assigned to either the avatar group (identified avatar) or the control group (anonymous avatar). Prior to training, participants completed a demographic questionnaire and a pretraining knowledge assessment. TMJ training was conducted in the metaverse for both groups. Pre- and post-training assessments included the Spielberger State-Trait Anxiety Inventory and a shyness scale to ensure group comparability. A post-test consisting of five questions was administered to both groups after 2 weeks of training.ResultsThere were no significant differences in pretraining scores for prior knowledge (p = 0.67), trait anxiety (p = 0.28), state anxiety (p = 0.92), or shyness (p = 0.42) between the avatar and control groups, indicating comparability at baseline. Post-training analysis revealed significantly higher post-test scores in the avatar group (median = 80) compared to the control group (median = 60) (p = 0.03).ConclusionsMetaverse environments offer various benefits for students, educators, and educational institutions in health education programs. Representing learners and their identities in training environments can enhance learning outcomes.Article Citation - WoS: 14Citation - Scopus: 15Yielding of Two-Layer Shrink-Fitted Composite Tubes Subject To Radial Pressure(Springer Heidelberg, 2005) Eraslan, AN; Akis, TYielding of two-layer shrink-fitted composite tubes with axially constrained ends subject to either internal or external pressure is investigated in detail. In the framework of small deformations, a state of plane strain and von Mises yield criterion, analytical expressions are obtained for critical values of the pressure leading to plastic flow. It is shown that, depending on material properties and tube dimensions, different modes of plastic deformation may occur. Yielding may commence at the inner tube or at the outer tube or simultaneously in both tubes. The conditions for different nature of plastic flow are determined. Using analytical expressions obtained for critical values of the parameters and properties of real engineering materials, various numerical examples are handled and the variation of elastic limit pressure with interference and interface radius is explained.Article Citation - WoS: 36Citation - Scopus: 44Lyapunov-Type Inequalities for Mixed Non-Linear Forced Differential Equations Within Conformable Derivatives(Springer, 2018) Abdeljawad, Thabet; Agarwal, Ravi P.; Alzabut, Jehad; Jarad, Fahd; Ozbekler, AbdullahWe state and prove new generalized Lyapunov-type and Hartman-type inequalities fora conformable boundary value problem of order alpha is an element of (1,2] with mixed non-linearities of the form ((T alpha X)-X-a)(t) + r(1)(t)vertical bar X(t)vertical bar(eta-1) X(t) + r(2)(t)vertical bar x(t)vertical bar(delta-1) X(t) = g(t), t is an element of (a, b), satisfying the Dirichlet boundary conditions x(a) = x(b) = 0, where r(1), r(2), and g are real-valued integrable functions, and the non-linearities satisfy the conditions 0 < eta < 1 < delta < 2. Moreover, Lyapunov-type and Hartman-type inequalities are obtained when the conformable derivative T-alpha(a) is replaced by a sequential conformable derivative T-alpha(a) circle T-alpha(a), alpha is an element of (1/2,1]. The potential functions r(1), r(2) as well as the forcing term g require no sign restrictions. The obtained inequalities generalize some existing results in the literature.Article Citation - WoS: 6Citation - Scopus: 6Does Overparenting Hurt Working Turkish Mother's Well-Being? the Influence of Family-Work Conflict and Perceived Stress in Established Adulthood(Springer/plenum Publishers, 2023) Aydin, Eren Miski; Metin-Orta, Irem; Metin-Camgoz, Selin; Aksan, NazanAlthough extant research demonstrates the negative impact of overparenting on child well-being, there remains a paucity of evidence on the effect of overparenting on the parents' own well-being. The purpose of this study is to investigate the effects of overparenting on parental well-being, and to explore the mechanisms through which overparenting influences the well-being of working mothers, particularly among established adults. Thus, we examined the serial mediation effects of perceived stress and family-to-work conflict (FWC) in overparenting and well-being linkage. With this aim, the data were collected from working mothers (N = 258) aged between 30 and 45, a period of in their lifespan generally characterized by efforts devoted to career and care. Via serial mediation analyses, the findings postulate that (a) overparenting relates to the well-being and perceived stress of working mothers, (b) perceived stress (both individually and jointly with FWC) mediates the relationship between overparenting and well-being, and (c) perceived stress and FWC serially mediate the association between overparenting and well-being. The findings provide evidence related to the well-being experiences of established adulthood women in struggling their career-and care crunch from a perspective of overparenting, stress, and family-to-work conflict.
