Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Optimization of Fleet Search on Network of Regions(Elsevier Ltd, 2026) Yakıcı, E.; Erişkin, L.; Karatas, M.; Karasakal, O.Unmanned Aerial Vehicles (UAVs) are widely used in modern military missions, primarily for surveillance, reconnaissance, search and detection, and air-to-ground strikes. The widespread use of UAVs in recent conflicts, such as the Russia–Ukraine war, once again highlighted their growing strategic importance. The complexity of military missions carried out by UAVs, coupled with the need for autonomous and coordinated fleet operations, requires analytical approaches to optimize deployment planning and improve operational efficiency. In this study, we address a UAV deployment planning problem for search and detection missions, in which a homogeneous fleet of UAVs is tasked with searching for hostile assets across a network of disjoint regions. Each region is characterized by an a priori probability of target presence, a search difficulty factor which affects the probability of detection, and known inter-region distances. For this purpose, we first develop a mixed-integer nonlinear programming formulation which determines the base locations of UAVs, allocates the limited search time across regions, and sequences the visits to maximize the total time-weighted detection probability mass to achieve the highest probability as much and as early as possible during the operation. Next, we apply a tangent line approximation technique to reformulate the model as a mixed-integer linear programming problem, which we solve using commercial off-the-shelf solvers. We then propose a hybrid heuristic approach based on the ant colony optimization method to generate high-quality solutions. Our computational experiments reveal that the proposed heuristic significantly reduces solution time while maintaining superior performance compared to the linear approximation model. © 2026 The AuthorsArticle Citation - WoS: 1Citation - Scopus: 1Enhancement of Brazing Performance of Inconel 718 By Electroless Cobalt Coated Nickel-Based Brazing Alloys(Elsevier, 2025) Goynuk, Tansu; Esen, Ziya; Karakaya, IshakEffect of electroless cobalt-coated BNi-2 on the brazing performance of Inconel 718 was investigated in this study. A new method for modifying the microstructure and thermal properties of brazing alloys by incorporating cobalt through electroless deposition was introduced. This approach offers a more controlled and uniform alloy modification compared to conventional mechanical mixing techniques, enhancing the performance of the brazed joints. The introduction of cobalt into the filler material influences the microstructural evolution and refining the joint structure by reducing brittle precipitates. Microstructural analysis confirms that the Co-coated BNi-2 results in a more homogeneous joint with improved phase distribution. Mechanical characterization indicated that the shear strength increased nearly 4.5 times, while fracture strain improved approximately fourfold. Moreover, the cobalt addition raised the solidus temperature of the filler alloy by 25-30 degrees C, contributing to better high-temperature stability. These findings highlight the effectiveness of electroless cobalt coating in optimizing brazing alloys for demanding aerospace and high-temperature applications.Article Influencers in Luxury Brand Communication: An Evaluation of the Relationship Between Source Credibility, Persuasive Message, and Parasocial Engagement(Sage Publications Inc, 2025) Alkan, Zeynep; Dolunay, Ayhan; Ulas, SevilayThis study examines persuasive messages and source credibility in luxury brand influencers' content within their brand collaborations. It also explores how influencers establish parasocial engagement with followers through their posts. Conducted as an online survey between February and July 2023, the study targeted 400 individuals in Northern Cyprus who follow influencers. Findings indicate that increased parasocial engagement enhances the perceived persuasiveness of messages. A positive relationship between parasocial engagement and source credibility was observed, demonstrating that as influencers' credibility rises, so does the persuasiveness of their messages. Additionally, the study analyzed relationships between parasocial engagement, persuasive messages, source credibility and demographic factors. While no significant differences were found between parasocial engagement and most demographic characteristics, education level stood out. Individuals with a primary education level showed a greater tendency toward parasocial engagement. A significant difference was noted between source credibility and monthly income, with the highest perceived credibility reported in the 7,000 to 8,999 TL income group. Similarly, persuasive messages were most effective among individuals in this income range. In conclusion, this study highlights the importance of considering demographic differences and parasocial engagement in influencer brand collaborations. It underscores that source credibility and persuasive messages play a crucial role in influencer communication, influencing how audiences perceive and engage with branded content. It has been concluded that strong parasocial bonds in influencer and brand collaborations play a strategic role in establishing effective interaction with the target audience.Article Citation - WoS: 5Citation - Scopus: 6A Review of Passive Design Strategies and Their Effect on Thermal Resilience in Low-Income Households(Elsevier Science S.A., 2025) Kokatnur, Tejas; Ferreira, Shane; Akkoc, Busra Karadeniz; Markarian, Elin; Nojedehi, Pedram; Qiblawi, Seif; Azar, ElieClimate change is causing more frequent and extreme weather events (e.g., heat waves and ice storms) that disproportionately impact low-income households with poor building conditions. Passive design strategies offer a promising solution to enhance building thermal resilience; however, little is known about their actual application and effectiveness in low-income households under different climate conditions. This paper presents a scoping literature review of 123 articles that evaluated passive design strategies applied to low-income housing contexts. The detailed article review shows that wall-and roof-related passive design strategies (e.g., insulation, sealing) are the most frequently studied and effective strategies, increasing comfort hours and energy savings with a wide variation of up to 24 % and 67 %, respectively. Combined strategies often outperformed individual strategies. In contrast, some studies reported unintended consequences following the adoption of passive design strategies, such as increases in energy demand reaching as high as 50 %. Such findings shed light on the need for design processes to consider multiple performance metrics, as well as behavioural and socio-economic factors that require more in-depth investigation, such as energy poverty and rebound effects. Detailed recommendations are finally provided to guide future research and applications on the topic, covering the need to (i) explore and combine underrepresented thermal resilience strategies and metrics, (ii) follow more standardized reporting practices, (iii) quantify costs and identify implementation barriers, and (iv) integrate participatory research methods to support technical assessments with contextual knowledge of the studied low-income households and communities.Article Citation - WoS: 6Citation - Scopus: 6Modeling the Transmission Dynamics of Middle Eastern Respiratory Syndrome Coronavirus with the Impact of Media Coverage(Elsevier, 2021) Fatima, BiBi; Alqudah, Manar A.; Zaman, Gul; Jarad, Fahd; Abdeljawad, ThabetMiddle East respiratory syndrome coronavirus has been persistent in the Middle East region since 2012. In this paper, we propose a deterministic mathematical model to investigate the effect of media coverage on the transmission and control of Middle Eastern respiratory syndrome coronavirus disease. In order to do this we develop model formulation. Basic reproduction number R-0 will be calculated from the model to assess the transmissibility of the (MERS-CoV). We discuss the existence of backward bifurcation for some range of parameters. We also show stability of the model to figure out the stability condition and impact of media coverage. We show a special case of the model for which the endemic equilibrium is globally asymptotically stable. Finally all the theoretical results will be verified with the help of numerical simulation for easy understanding.Article Citation - WoS: 1Citation - Scopus: 2Testing the Equality of Several Independent Stationary and Non-Stationary Time Series Models with Fractional Brownian Motion Errors(Elsevier, 2021) Mahmoudi, Mohammad Reza; Baleanu, Dumitru; Qasem, Sultan Noman; Mosavi, Amirhosein; Band, Shahab S.; S. Band, ShahabThis work is devoted to apply the parametric and nonparametric techniques to construct test of hypothesis about the equality of the probabilistic behaviors of several time series models with fractional Brownian motion errors fitted on several independent datasets. The accuracy and power of the introduced method are studied using the simulated and real datasets. The results indicate that the introduced approach is more powerful than other alternative approaches, in non-stationary cases. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Article Citation - WoS: 180Citation - Scopus: 192On Fractional Calculus with General Analytic Kernels(Elsevier Science Inc, 2019) Fernandez, Arran; Ozarslan, Mehmet Ali; Baleanu, DumitruMany possible definitions have been proposed for fractional derivatives and integrals, starting from the classical Riemann-Liouville formula and its generalisations and modifying it by replacing the power function kernel with other kernel functions. We demonstrate, under some assumptions, how all of these modifications can be considered as special cases of a single, unifying, model of fractional calculus. We provide a fundamental connection with classical fractional calculus by writing these general fractional operators in terms of the original Riemann-Liouville fractional integral operator. We also consider inversion properties of the new operators, prove analogues of the Leibniz and chain rules in this model of fractional calculus, and solve some fractional differential equations using the new operators. (C) 2019 Elsevier Inc. All rights reserved.Article Citation - WoS: 3Citation - Scopus: 3Existence Results for Block Matrix Operator of Fractional Orders in Banach Algebras(MDPI, 2019) Hashem, Hind; El-Sayed, Ahmed; Baleanu, DumitruThis paper is concerned with proving the existence of solutions for a coupled system of quadratic integral equations of fractional order in Banach algebras. This result is a direct application of a fixed point theorem of Banach algebras. Some particular cases, examples and remarks are illustrated. Finally, the stability of solutions for that coupled system are studied.Editorial Introduction to the Special Issue on Mathematical Aspects of Computational Biology and Bioinformatics-I(Tech Science Press, 2023) Baleanu, Dumitru; Pinto, Carla M. A.; Kumar, SunilArticle An Improvement in the Design Process of Sustainable Peak Power Rating Transformer for Solar Utility(Elsevier Sci Ltd, 2025) Yukselen, Emir; Rahimpour, EbrahimThe transformer industry faces critical challenges, such as maintaining reliable production while meeting rising sustainability requirements. This paper introduces a significant advancement in the design and optimization of a transformer dedicated to a photovoltaic power plant, which exhibits a unique loading cycle distinct from standard power and distribution transformers. The main aim is to minimize the carbon footprint by enhancing the design process to improve operational performance, efficiency, and functional reliability. Such upgrades are essential for transitioning to a zero-emission electricity system and developing green energy projects. In this paper, a transformer has been studied using a combination of electrical design and 3D finite element method simulation to evaluate various design parameters. An optimization study has been conducted using an innovative multi-objective genetic algorithm utilizing a cost function that factors in size and material costs to identify the most efficient and cost-effective design solutions. The proposed design method was then validated through thermal model simulations and experimental tests based on the photovoltaic load cycle. A comparison of critical thermal parameters directly affecting the transformer's lifetime and reliability was also drawn. The results were consistent with the expected outcomes, confirming the effectiveness and reliability of the proposed design methodology.