6 results
Search Results
Now showing 1 - 6 of 6
Article Isometric Representations of Calibrated Ordered Spaces on C(X)(Ankara University, Fac Sci, 2025) Ay, SerdarThe problem of characterizing normed ordered spaces which admit a representation in the algebraic, order and norm sense as a subspace of $C(X)$, the space of all continuous functions on a compact Hausdorff space is a classical problem that has been considered by many authors. In this article we consider the more general case of calibrated ordered spaces, that is, ordered spaces with a specified family of seminorms generating its topology. For such spaces equivalent conditions on representability as a subspace of $C(X)$ for some locally compact Hausdorff space $X$, in the algebraic, order and seminorm sense are stated and proved. Some characterizations appear to be new even in the normed case. A recent result on isometric representations of locally ordered spaces fall under the results in this paper with more general statements. As an application of the main theorems, we state and prove a characterization of norm additivity property of two positive functionals.Article Analytic Hierarchy Process in Determining Aircraft Basic Maintenance Training Durations(Emerald Publishing, 2025) Açıkel, Gürkan; Alemdaroğlu Temel, MinePurpose – Currently, in aircraft basic maintenance training, it is determined that various aircraft basic maintenance training organizations around the world apply different basic maintenance durations for the same modules of the same licence categories. Aircraft basic maintenance training organizations are lacking a common curriculum with standard durations for the basic maintenance training modules. To remedy the problems associated with this issue, the purpose of this study is to develop and demonstrate a quantifiable reference (i.e. theoretical training and evaluation content intensity) based scientific theoretical method to determine the durations of the basic theoretical maintenance trainings held for B1.1 and B2 licence categories in aircraft basic maintenance training organizations. Design/methodology/approach – The total basic maintenance training duration was first allocated to basic, theoretical and practical maintenance trainings. The obtained basic theoretical maintenance training duration was then allocated to related modules and submodules by using weighted theoretical training content intensity and weighted theoretical evaluation content intensity, which were obtained by applying a multi-criteria decision-making approach using the analytic hierarchy process (AHP). Findings – In this study, it was found that there is no standardization upon aircraft basic maintenance training organizations for the allocation of the basic maintenance training durations to modules. To remedy this problem, a scientific method, which relies on quantifiable reference bases rather than subjective reasoning, is needed. The reference bases of the proposed theoretical method (i.e. theoretical training and evaluation content intensity) can be tuned with the inclusion of the effect of basic knowledge requirements through multi-criteria decision-making (AHP). The theoretical method proposed in this work is robust in terms of resulting in close proximity values of the basic theoretical maintenance training durations for the common modules of B1.1 and B2 licence categories. The theoretical method is proven to yield greater basic theoretical maintenance training durations for modules having greater theoretical training and evaluation content intensity and lower basic theoretical maintenance training durations for modules having less theoretical training and evaluation content intensity. A distinct similarity in terms of basic theoretical maintenance training durations and the ranking of the modules (in terms of durations) is not present when the average of the training organizations is compared to the results of the theoretical method. A quantifiable reference (i.e. theoretical training and evaluation content intensity) based scientific theoretical method to determine basic theoretical maintenance training durations was developed and demonstrated. Practical implications – Results of this study would especially be useful in an international effort to standardize the different basic theoretical maintenance training durations applied in various aircraft basic maintenance training organizations. Originality/value – To the best of the authors’ knowledge, this study is the first in providing and demonstrating a scientific theoretical method based on a systematic, multi-criteria decision-making approach to determine the durations of the basic theoretical maintenance trainings. © 2025 Elsevier B.V., All rights reserved.Article An Updated Meta-Analysis on the Association Between Celiac Disease and Cardiovascular Diseases(E-Century Publishing Corp, 2025) Faraji, Mahdi; Khademi, Reza; Maleki, Maede; Jafari, Fatemeh; Olama, Ensiyeh; Saghafi, Mohammad Sadra; Anar, Mahsa AsadiObjectives: Research on the relationship between celiac disease (CD) and cardiovascular disease (CVD) is still ongoing, and different studies have reported contradictory findings. To carry out a meta-analysis and systematic review to look into the connection between CD and CVD risk. Methods: A thorough search was conducted in PubMed, Scopus, and Google Scholar databases up to February 19, 2024. Relevant articles were extracted, and the titles, abstracts, and full texts of the related articles were screened. The quality of the studies was assessed using the Joanna Briggs Institute critical appraisal tools. Results: Nine cohort and one case-control studies involving 49,621,333 individuals were included in the meta-analysis. The pooled analysis revealed a 7% increased risk of CVD in CD patients compared to controls (OR: 1.07, 95% CI: 1.03-1.10, P < 0.05). Significant heterogeneity was observed among studies (I2 = 76%, P < 0.001). Conclusion: This meta-analysis provides evidence of a modest but significant increase in CVD risk in patients with CD. The results highlight the importance of considering cardiovascular health in CD treatment and the need for further research to elucidate the mechanisms underlying this association and to develop targeted prevention strategies.Article An Application of Stochastic Maximum Principle for a Constrained System With Memory(Ankara Univ, Fac Sci, 2025) Savku, EmelIn this research article, we study a stochastic control problem in a theoretical frame to solve a constrained task under memory impact. The nature of memory is modeled by Stochastic Differential Delay Equations and our state process evolves according to a jump-diffusion process with time-delay. We work on two specific types of constraints, which are described in the stochastic control problem as running gain components. We develop two theorems for corresponding deterministic and stochastic Lagrange multipliers. Furthermore, these theorems are applicable to a wide range of continuous-time stochastic optimal control problems in a diversified scientific area such as Operations Research, Biology, Computer Science, Engineering and Finance. Here, in this work, we apply our results to a financial application to investigate the optimal consumption process of a company via its wealth process with historical performance. We utilize the stochastic maximum principle, which is one of the main methods of continuous-time Stochastic Optimal Control theory. Moreover, we compute a real-valued Lagrange multiplier and clarify the relation between this value and the specified constraint.Article QRS (Quality-Reliability-Safety) Complex of Engineering: Its Importance and Necessity in Engineering Education(SAGE Publications Inc., 2026) Eryilmaz, S.Although quality, reliability and safety are well-known concepts, the importance of these concepts has increased even more considering today's technologies and integrated systems. It is important that these concepts are known by engineers who play an important role in the design of such systems. This article aims to emphasize the importance and necessity of teaching the triple of quality, reliability and safety, expressed with the acronym QRS, in engineering education. In particular, the definitions of these concepts, the relationships between them and the basic issues that should be known by any engineering student regarding these concepts are summarized. Some suggestions are offered to help engineering students gain competence in these subjects. © The Author(s) 2026Article Randomised Comparison Between Navigation and Non-Navigation Camera Control Performance in a Surgical Simulation Task Using a Haptic Device Interface(Wolters Kluwer Medknow Publications, 2026) Cagiltay, Nergiz Ercil; Topalli, Damla; Tuner, Emre; Berker, MustafaIntroduction:Navigation skills for controlling the camera in the surgical field are critical for many minimally invasive surgery (MIS) procedures. Currently, endoscopes lack integrated navigation aids, making camera control a challenging task. This experimental study aims to investigate the effect of navigation guidance on the performance of beginners.Patients and Methods:A custom computer-based simulation environment was developed for this study, featuring two conditions - one with navigation guidance and one without - focussed on a camera-cleaning task. Participants (64 beginners) were randomly assigned to one of these groups and used two haptic devices to simulate the endoscope and surgical tools.Results:Participants in the guided condition performed significantly better than those in the unguided condition. Notably, female participants completed the task in significantly less time under the guided condition compared to the unguided one.Conclusion:These findings suggest that incorporating navigation aids into endoscope interfaces could improve user performance, especially for beginners. Medical device manufacturers should consider adding navigation features to enhance usability. In addition, simulation-based instructional systems should integrate navigation aids to better support surgical training.
