Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Surface Integrity and Tool Wear in S2-GFRP Milling: Experimental and Statistical Evaluation of Cutting Parameters and DLC and TiAlN Tool Coatings(Springer London Ltd, 2026) Danisman, Sengul; Yilmaz, Cagatay; Ersoy, Emin; Kesriklioglu, SinanIn this study, the surface integrity of S2-glass fiber-reinforced polymer (S2-GFRP) composites during milling with carbide cutters was investigated using a two-phase experimental design, focusing on surface roughness (Ra), burr area, and tool wear (VB). In the first phase, using a Taguchi L9 design, the effects of coating type (uncoated, TiAlN, DLC), spindle speed (2000-6000 rpm), and feed rate (0,15-0,25 mm/rev) on Ra and burr area were evaluated. In this short machining range where tool wear was negligible, the optimal combination yielding the lowest Ra (approximate to 0.97 mu m) and the minimum burr area (approximate to 231 mm & sup2;) was determined to be 4000 rpm, 0,15 mm/rev, and the DLC-coated tool. Regarding the effect of tool material on Ra, the DLC-coated tool provided approximately 4 and 2 times better results than the uncoated and TiAlN-coated tools, respectively. In the second phase, experiments extended up to 130 passes with this optimal parameter set showed that Ra increased significantly with increasing VB, and the burr area exhibited threshold-like behavior. In particular, a sudden increase in Ra and the burr area was observed when the VB approximate to threshold of approximately 100 mu m was exceeded; partial regression analyses confirmed different burr-formation tendencies in the low- and high-wear regimes. The results reveal that DLC coating initially provides superior performance in S2-GFRP milling, but surface degradation accelerates after the critical VB threshold.Article Structural Optimization for Robotic Concrete Construction: A Systematic Review(MDPI, 2026) Gürer, Ethem; Pektaş, Ömer Korkut; Alaçam, Sema; Güzelci, Orkan Zeynel; Çevik, Ayşe Nesligül; Türel, Ahmet; Özdemir, SalihConcrete construction is associated with high environmental impact and geometric limitations imposed by conventional formwork, which has led to growing interest in combining structural optimization with robotic fabrication. In this study, structural optimization refers to computational methods such as topology optimization, shape optimization, and form finding that aim to improve material efficiency and load-bearing performance by modifying the geometry of structural elements. This systematic review investigates how these optimization approaches are translated into fabrication-aware design workflows for robotic concrete construction. Following a PRISMA-based methodology, 90 peer-reviewed studies published between 2015 and 2025 were analyzed. The review focuses on fabrication routes including (i) 3D concrete printing, (ii) 3D-printed formwork, (iii) shotcrete-based additive manufacturing, and (iv) controlled casting systems, and examines how each route constrains geometry representation, design decisions, toolpath generation, and robotic execution. The review analyzes design-to-fabrication workflows that link optimized structural geometry to production logic and process control. Key findings indicate that incorporating fabrication constraints at early design stages can support buildability and potential material efficiency, while reinforcement integration and quality control remain critical challenges for structural reliability. The review also highlights the increasing role of in situ sensing and feedback-driven automation in improving process stability. Overall, the study clarifies current practices, limitations, and emerging directions for integrating structural optimization with robotic concrete fabrication.Article From Agility to Advocacy: Exploring How Gender Moderates the Impact of Social Media Agility on Brand Trust and Influencing Behavior(Palgrave Macmillan Ltd, 2026) Bozkurt, Sıddık; Gligor, David; Hollebeek, Linda D.; Sarp, SerapThis research investigates the effect of perceived social media agility (P-SMA) on customers' influencing behavior, a theoretical subset of engagement behavior, with brand trust acting as a mediator and gender (male/female) as a moderator. It also explores how these relationships differ across age groups. Two online surveys were conducted: Study 1 with 165 younger participants and Study 2 with 178 adults. Using PROCESS Macro Models 4 and 7, we tested direct, mediated, and moderated mediation effects. Both studies found that P-SMA enhances brand trust, which subsequently mediates its influence on customer behavior. Study 2 confirmed these results, showing that gender moderates the relationship between P-SMA and both brand trust and influencing behavior, with stronger effects observed among females (vs. males) in both samples. The findings highlight the importance of tailoring social media strategies to gender-based engagement patterns. Crafting content and interaction styles that foster trust can improve influence and advocacy, especially when agility is a key element of the brand's digital presence. This research integrates P-SMA, brand trust, and customer influence behavior within a moderated mediation model. Using two age-diverse samples, it shows gender shapes reactions to brand agility, while age differences remain non-significant across both datasets.Article Radar Resolution Enhancement Based on Burg-Aided MIMO-DBS and Burg-Aided MIMO-SAR †(MDPI, 2026) Bekar, Muge; Bekar, Ali; Baker, Christopher John; Gashinova, Marina; Pirkani, AnumAutonomous systems require sensors that provide high-resolution imagery in adverse lighting and weather conditions for advanced situational awareness. In this regard, radars are a mandatory component of autonomous systems. Although Multiple-Input Multiple-Output (MIMO) radars provide high angular resolution beyond that of their actual physical dimension, much higher cross-range resolutions are required, especially in traffic congested areas, to differentiate and recognize closely positioned targets. The motion of the MIMO radar platform can be exploited to obtain higher cross-range resolution in the off-boresight direction, using Synthetic Aperture Radar (SAR) and Doppler Beam Sharpening (DBS) techniques, but improvements in the boresight direction, the most crucial direction for path planning, require the use of super-resolution techniques. This paper proposes a technique that combines the Burg algorithm with MIMO-SAR and MIMO-DBS radar data to enhance the cross-range resolution in the boresight direction and to achieve further enhanced cross-range resolution in off-boresight directions. The proposed technique is applied to both frequency domain and time domain data in back-projection (BP) and DBS image formation processing. A comprehensive comparison is made, with evaluation of corresponding performance and operational complexity. The performance of the technique is validated through simulation, lab-based and real-world experiments at a frequency of 77 GHz.Article Experimental Comparative Analysis of Hole-Making Strategies and Cutting Parameters on Flexural Properties and Induced Delamination in S2 Glass and Basalt Fiber-Reinforced Polymers(John Wiley and Sons Inc, 2026) Eltahir, Sara Saeed Abdulrahman; Yilmaz, Cagatay; Kesriklioglu, SinanOpen holes are often required in the applications of fiber-reinforced polymers (FRP). However, machining them leads to fiber and matrix damage, reducing the overall quality of composites. The novelty of this study lies in investigating the influence of multiple hole machining strategies under varying feed rates and cutting speeds on the flexural strength, chord modulus and hole quality for S2-Glass (S2-GFRP) and basalt fiber-reinforced polymers (BFRP), followed by three-point bending tests and statistical analysis to determine the optimum machining parameters in terms of flexural properties, delamination, and time efficiency. Findings indicate that conventional milling yields an increase in the flexural strength and chord modulus by 22.2 MPa and 1.9 GPa, respectively, for S2 GFRP. While climb milling performs best for BFRP, enhancing flexural performance by 7.6 MPa and 0.4 GPa. Direct drilling at high feed rate and cutting speed shows the poorest performance. Hole machining at low feed rate using climb milling minimizes delamination at the entrance by 14.8% for S2 GFRP and by 2.7% for BFRP using conventional milling. At the exit, helical milling at a low feed rate suppresses delamination damage by 58.5% and 10.7% for S2 GFRP and BFRP. The most time-efficient method is direct drilling at a feed rate of 0.075 mm/rev and cutting speed of 75 m/min or climb milling with same feed rate, but 25 m/min cutting speed. Within the tested ranges, the optimized drilling setup significantly improved structural performance of S2-GFRP and GFRP, confirming the effectiveness of the proposed experimental-statistical framework.Article Performance Evaluation of Multi-Modal Radar Signal Processing in Dense Co-Existent Environments(MDPI, 2026) Norouzian, Fatemeh; Bekar, Muge; Bekar, Ali; Gashinova, Marina; Pirkani, AnumThe wide-scale deployment of radars, distributed across a platform and across multiple platforms for reliable 360 degrees situational awareness (SA), introduces the challenge of radar interference. Interference can broadly be categorised as self-interference (between radars mounted on the same platform) and mutual interference (signals received from radars on other platforms). Both types of interference impede the reliability of SA delivered by such systems, particularly in dense environments where numerous radars operate simultaneously within the same frequency band. This work presents a comprehensive evaluation of a multi-modal beamforming approach that combines unfocused synthetic aperture radar with the traditional Multiple-Input, Multiple-Output beamformer to enhance radar resolution and suppress interference. Additionally, various aspects of sensor configurations defining hardware and software capabilities of state-of-the-art radars are discussed, and a systematic analysis of signal-to-interference-plus-noise ratio at each step of the processing is presented. Extensive simulations and experimental results in both automotive and maritime environments are shown to validate the effectiveness of the proposed approach.Article Enhanced Mg–Zn–Ca Alloys Reinforced with Rare Earth Oxides for Biomedical Applications: Experimental Insights and ANFIS-Based Modeling(Springer, 2026) Mozafari, Farzin; Deka, Surja; Mallick, AshisTo enhance the corrosion resistance, biocompatibility, tribological, and mechanical properties of magnesium (Mg) alloys intended for biomedical implants, a new approach utilizing a microwave-sintered in situ hot extrusion-based powder metallurgy process was used to develop Mg-4Zn-0.5Ca/xCeO2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document} (x = 0.5, 1, and 1.5 vol%) nanocomposites. The introduction of ceria nanoparticles (CONPs) has improved the compression characteristics of the nanocomposites in comparison with the monolithic Mg, and the ternary base alloy. The corrosion test results revealed that the alloy and nanocomposites promoted the formation of the magnesium hydroxide (Mg(OH)2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document}) and hydroxyapatite (HA) layers on the sample surface. Among all samples, Mg-4Zn-0.5Ca /1.0CeO2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_2$$\end{document} demonstrated the lowest corrosion rate. In vitro cytocompatibility assessments were conducted through an extract assay method for different time periods, employing MG-63 cells. The developed alloy and nanocomposites demonstrated no harmful effects on MG-63 cells. An investigation into the dry sliding tribological characteristics of the alloy and nanocomposites at varied loads revealed several wear mechanisms, including abrasion, adhesion, delamination, oxidation, and plastic deformation. The addition of CONPs significantly enhanced the wear resistance of the nanocomposites. Our results provide a new venue to enhance the biocompatibility and in vitro degradation behavior of well-established Mg-Zn-Ca alloys, with a particular focus on the mechanical integrity of the developed samples for their clinical usage. An Adaptive Neuro-Fuzzy Inference system (ANFIS)-based modeling approach was also developed to individually characterize nanocomposite corrosion, cell viability, and wear behavior. The predictions offer compelling evidence of the reliability and accuracy of the proposed modeling strategy.Article Environmental Sustainability in Fragile States: The Role of Corruption Control, Political Stability, and Household Consumption in Somalia(Springer, 2026-03-28) Mohamed, Amir Mohamud; Warsame, Abdimalik Ali; Dirie, Khadar AhmedThe maintenance of environmental sustainability represents a worldwide pressing issue, especially for Somalia as an emerging nation that deals with environmental degradation because of unstable political leadership combined with corruption and financial limitations. This study analyzes the impact of corruption control, political stability, and household consumption on environmental degradation in Somalia. The study employs the kernel regularized machine learning method (KRLS) and a time-varying Granger causality approach. The KRLS addresses regression and classification tasks without depending on assumptions of linearity or additivity, whereas the time-varying Granger causality fixes instabilities caused by structural breaks, regime shifts, and provides a cause-effect relationships for specific years. The empirical results of the KRLS indicate that corruption control enhances environmental quality by reducing environmental degradation, whereas household consumption impedes it. Additionally, political stability has no discernible impact on environmental degradation. The time-varying Granger causality result revealed no significant causality from corruption control to environmental degradation in the forward and rolling windows. Two episodes of Granger causalities (2009-2011 and 2013-2016) are observed from corruption control to environmental degradation, and one episode of causality (2001-2004) from political stability to environmental degradation was detected in the recursive result. Finally, four episodes of causalities (2005-2007, 2008-2011, and 2014-2015) are observed from household consumption to environmental degradation in Somalia in the recursive result. This could be justified by the fact that climate consequences-droughts and floods-inhibit livelihood sources such as livestock and agriculture. Hence, people put pressure on forests in search of alternative income sources. Nevertheless, the study delivers practical recommendations to policymakers about using governance structures and economic decisions along with institutional mechanisms for creating sustainable environmental practices.Article Citation - Scopus: 4RCE-IFE: Recursive Cluster Elimination with Intra-Cluster Feature Elimination(PeerJ Inc., 2025-02-07) Kuzudisli, Cihan; Bakir-Gungor, Burcu; Qaqish, Bahjat; Yousef, MalikArticle Citation - Scopus: 7Network Anomaly Detection Using Deep Autoencoder and Parallel Artificial Bee Colony Algorithm-Trained Neural Network(PeerJ Inc., 2024-10-08) Dedeturk, Bilge Kagan; Bakir-Gungor, Burcu; Hacılar, Hilal; Gungor, Vehbi Cagri