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Article Citation - WoS: 27Citation - Scopus: 28Generalized Meir-Keeler Type Contractions on g-metric Spaces(Elsevier Science inc, 2013) Mustafa, Zead; Aydi, Hassen; Karapinar, ErdalIn this manuscript, we introduce generalized Meir-Keeler type contractions over G-metric spaces. Moreover, we show that every orbitally continuous generalized Meir-Keeler type contraction has a unique fixed point on complete G-metric spaces. We illustrate our results by some given examples. (C) 2013 Elsevier Inc. All rights reserved.Article Citation - WoS: 33Citation - Scopus: 37Discrete Sizing Optimization of Steel Trusses Under Multiple Displacement Constraints and Load Cases Using Guided Stochastic Search Technique(Springer, 2015) Azad, S. Kazemzadeh; Hasancebi, O.The guided stochastic search (GSS) is a computationally efficient design optimization technique, which is originally developed for discrete sizing optimization problems of steel trusses with a single displacement constraint under a single load case. The present study aims to investigate the GSS in a more general class of truss sizing optimization problems subject to multiple displacement constraints and load cases. To this end, enhancements of the GSS are proposed in the form of two alternative approaches that enable the technique to deal with multiple displacement/load cases. The first approach implements a methodology in which the most critical displacement direction is considered only when guiding the search process. The second approach, however, takes into account the cumulative effect of all the critical displacement directions in the course of optimization. Advantage of the integrated force method of structural analysis is also utilized for further reduction of the computational effort in these approaches. The proposed enhancements of GSS are investigated and compared with some selected techniques of design optimization through six truss structures that are sized for minimum weight. The numerical results reveal that both enhancements generally provide promising solutions with an insignificant computational effort.Article Citation - Scopus: 1A User Task Design Notation for Improved Software Design(PeerJ Inc., 2021) Ozcan,E.; Topalli,D.; Tokdemir,G.; Cagiltay,N.E.System design is recognized as one of the most critical components of a software system that bridges system requirements and coding. System design also has a significant impact on testing and maintenance activities, and on further improvements during the lifespan of the software system. Software design should reflect all necessary components of the requirements in a clear and understandable manner by all stakeholders of the software system. To distinguish system elements, separation of concerns in software design is suggested. In this respect, identification of the user tasks, i.e., the tasks that need to be performed by the user, is not currently reflected explicitly in system design documents. Our main assumption in this study is that software quality can be improved significantly by clearly identifying the user tasks from those that need to be performed by the computer system itself. Additionally, what we propose has the potential to better reflect the user requirements and main objectives of the system on the software design and thereby to improve software quality. The main aim of this study is to introduce a novel notation for software developers in the frame of UML Activity Diagram (UMLAD) that enables designers to identify the user tasks and define them separately from the system tasks. For this purpose, an extension of UML-AD, named UML-ADE (UML-Activity Diagram Extended) was proposed. Afterwards, it was implemented in a serious game case for which the specification of user tasks is extremely important. Finally, its effectiveness was analyzed and compared to UML-AD experimentally with 72 participants. The defect detection performance of the participants on both diagrams with two real-life serious game scenarios was evaluated. Results show a higher level of understandability for those using UML-ADE, which in turn may indicate a better design and higher software quality. The results encourage researchers to develop specific design representations dedicated to task design to improve system quality and to conduct further evaluations of the impact of these design on each of the above mentioned potential benefits for the software systems. © Copyright 2021 Ozcan et al.Article Citation - WoS: 31Citation - Scopus: 30Structure of the Ξb< Resonance(Amer Physical Soc, 2018) Aliev, T. M.; Azizi, K.; Sarac, Y.; Sundu, H.We explore the recently observed Xi(b)(6227)(-) resonance to fix its quantum numbers. To this end, we consider various possible scenarios: It can be considered as either a 1P or 2S excitation of the Xi(b) and Xi'(b)(5935) ground-state baryons with spin-1/2 or the 1P or 2S excitation of the ground-state Xi(b)(5955) with spin-3/2. We calculate the masses of the possible angular-orbital 1P and 2S excited states corresponding to each channel employing the QCD sum rule technique. It is seen that all the obtained masses are in agreement with the experimentally observed value, implying that the mass calculations are not enough to determine the quantum numbers of the state under question. Therefore, we extend the analysis to investigate the possible decays of the excited states into Lambda K-b(0)- and Xi(-)(b) pi. Using the light cone QCD sum rule method, we calculate the corresponding strong coupling constants, which are used to extract the decay widths of the modes under consideration. Our results on decay widths indicate that the Xi(b)(6227)(-) is a 1P angular-orbital excited state of the Xi(b)(5955) baryon with quantum numbers J(P) = 3/2(-).Article Citation - WoS: 27Citation - Scopus: 31Health Literacy of Nursing Students and Its Effective Factors(Wiley-hindawi, 2019) Ozen, Nurten; Ozkaptan, Bilge Bal; Coskun, Sabahat; Terzioglu, FusunBackground The insufficiency of health literacy negatively affects the national economy as it leads to increased health service expenditure. It is very important for individuals to have accurate health-related information to reduce these negative effects. Aim The aim of the study is to examine the health literacy of nursing students and its effective factors. Methods This descriptive study was carried out with students from the nursing department of a vocational school of health sciences between September and October 2018 in Turkey. A semi-structured questionnaire regarding the descriptive features of the participants and the European Health Literacy Scale were used for data collection. Results The study included 283 nursing students; 29.3% had a problematic-limited health literacy level. The study found a statically significant difference between student year, high school graduation and family's income level and the total mean score of the HLS-EU scale. Conclusion The subject of health literacy should be integrated into the educational program of nursing students. The nurses are the most important workforce in health services, and awareness about this subject should be raised.Article Citation - WoS: 6Citation - Scopus: 10Male and Female Differences in the Use of Social Media for Learning Purposes(Routledge Journals, Taylor & Francis Ltd, 2018) Akman, Ibrahim; Turhan, CigdemThis study aims to explore the differences between male and female users' behaviour with regard to acceptance of social media for learning in higher educational institutions. For this purpose, a survey was conducted and the least square regression analysis approach was utilised to investigate the relationships among the constructs in the research model for male and female users from a general and ethical perspective, focusing on the reliability, performance and awareness factors. The findings from the analysis reveal that a significant degree of diversity is present in the factors represented by general reliability', ethical reliability', ethical performance', ethical awareness' and ethical intention'.Article Citation - WoS: 1Citation - Scopus: 2On Locally Graded Barely Transitive Groups(versita, 2013) Betin, Cansu; Kuzucuoglu, MahmutWe show that a barely transitive group is totally imprimitive if and only if it is locally graded. Moreover, we obtain the description of a barely transitive group G for the case G has a cyclic subgroup aOE (c) x > which intersects non-trivially with all subgroups and for the case a point stabilizer H of G has a subgroup H (1) of finite index in H satisfying the identity chi(H (1)) = 1, where chi is a multi-linear commutator of weight w.Article Effectiveness of Boric Acid in Sepsis in Rats With Cecal Perforation(Springer Nature, 2025) Kurtipek, Ali Can; Dursun, Ali Dogan; Yigman, Zeynep; Ozdemir, Cagri; Kucuk, Aysegul; Gonullu, Ugur; Arslan, MustafaIntroduction and AimSepsis is a systemic inflammatory response that develops in the host against microorganisms, which results in end-organ damage. Boric acid (BA) has been shown to have immune modulatory effects in vitro and in animal studies. The aim of the study is to investigate the effects of high dose BA on lung and kidney tissues in rats with sepsis induced by the CLP method.Method28 rats were randomly divided into four groups: Group C (control group), Group BA, Group CLP (cecal ligation and puncture), and Group CLP + BA. Cecum was ligated below the ileocecal valve and punctured. BA was administered to the treatment groups at an intraperitoneal dose of 200 mg/kg, and at the end of 24 h, lung and kidney tissue samples were collected and evaluated for biochemical and histopathological parameters.ResultsHistopathologically, in kidney tissue, CLP + BA group showed significantly less peritubular capillary dilatation and brush border loss in the proximal tubule epithelium compared to the CLP group. In lung tissue, CLP + BA group had significantly less alveolar wall thickening compared to the CLP group. Biochemical analyses indicated that BA administration reduced oxidative stress in both renal and lung tissues.ConclusionWe found that intraperitoneal administration of high dose boric acid partially ameliorated the tissue damage in rats subjected to CLP induced sepsis. Further studies are needed regarding the dosage and application at different time points.Article Citation - WoS: 45Citation - Scopus: 49Recrystallization and Grain Growth Kinetics of In718 Manufactured by Laser Powder Bed Fusion(Elsevier, 2022) Dogu, Merve Nur; Davut, Kemal; Obeidi, Muhannad Ahmed; Yalcin, Mustafa Alp; Gu, Hengfeng; Low, Thaddeus Song En; Brabazon, DermotThe recrystallization and grain growth behaviour of IN718 alloy additively manufactured by laser powder bed fusion (L-PBF) is presented herein. The effects of three different temperatures (1050, 1150 and 1250 degrees C) and holding times (15, 45 and 90 min) were investigated. The texture evolution of the samples was recorded via electron backscatter diffraction (EBSD). The as-built sample is composed of bowl-shaped melt pools, a chessboard-like grain pattern and has a cube texture {100}<001>. Recrystallized grains were observed in the samples treated at 1150 degrees C for 15 min, as well as the samples treated for longer periods and at higher temperatures. Recrystallization was observed to start from high dislocation density regions, including the overlapping melt pools and the borders of the chessboard-like pattern. The initial cube texture transforms into a first-generation cube-twin texture {122}<212> via a twinning-assisted recrystallization mechanism. Then, those recrystallization nuclei sweep through the high defect density matrix; during which almost no new twins are formed. The samples treated at 1250 degrees C are almost completely recrystallized, which forms a weaker cube texture and a stronger P-orientation {011}<112>. However, the growth of recrystallized grains is very limited due to the presence of non-coherent precipitates. (C) 2022 The Author(s). Published by Elsevier B.V.Article Citation - WoS: 22Citation - Scopus: 25Effect of Solution Heat Treatment on the Microstructure and Crystallographic Texture of In939 Fabricated by Powder Bed Fusion-Laser Beam(Elsevier, 2023) Dogu, Merve Nur; Ozer, Seren; Yalcin, Mustafa Alp; Davut, Kemal; Bilgin, Guney Mert; Obeidi, Muhannad Ahmed; Brabazon, DermotThe effect of various solution heat treatment temperatures (i.e., 1120, 1160, 1200 and 1240 & DEG;C) on the microstructure, grain morphology and crystallographic texture of IN939 fabricated by powder bed fusion-laser beam (PBF-LB) was investigated. Microstructural analyses showed that the high-temperature gradient and rapid solidification of the PBF-LB processing caused different resulting microstructures compared to conventionally pro-duced counterparts. The melt pool morphologies and laser scanning paths were examined in the as-fabricated samples in the XZ-and XY-planes, respectively. After the application of solution heat treatment at 1120 & DEG;C, the as-fabricated PBF-LB initial microstructure was still apparent. For solution heat treatments of 1200 & DEG;C and above, the melt pool and scanning path morphologies disappeared and converted into a mixture of columnar grains in the XZ-plane and equiaxed grains in the XY-plane. On the other hand, large equiaxed grains were observed when the samples were solutionized at 1240 & DEG;C. Additionally, g' phase precipitated within the matrix after all solution heat treatment conditions, which led to increase in the microhardness values. According to electron backscatter diffraction (EBSD) analyses, both as-fabricated and solution heat-treated samples had intense texture with {001} plane normal parallel to the building direction. The first recrystallized grains began to appear when the samples were subjected to the solution heat treatment at 1160 & DEG;C and the fraction of the recrystallized grains increased with increasing temperature, as supported by kernel average misorientation (KAM) and grain spread orientation (GOS) analyses.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
