Browsing by Scopus Q Quality "Q4"

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    Analytical ETBDW Formulation for Electromagnetic Scattering by Circular Apertures on PMC Surfaces
    (Springer, 2025-12) Altınel, Mustafa; Yalçın, Uğur; 414019
    This study presents and validates a uniform analytical formulation for electromagnetic diffraction from circular apertures on perfect magnetic conductor (PMC) surfaces using the extended boundary diffraction wave (ETBDW) theory. The proposed PMC–ETBDW model incorporates an in-phase reflection coefficient ( = +1) within the boundary kernel, producing a physically continuous and energy-conserving representation of diffracted fields across illuminated, transition, and shadow regions. Expressed through detour parameters and Fresnel-type transition functions, the formulation eliminates phase discontinuities and maintains amplitude normalization consistent with theoretical energy conservation. Numerical evaluations performed for representative aperture radii (a = λ–3λ) and observation distances (r = 3λ–9λ) confirmed the expected 1/r amplitude decay, smooth Fresnel–Fraunhofer transitions, and constructive interference associated with magnetic reflection. Comparative analyses with PEC and opaque boundaries verified that in-phase magnetic reflection enhances on-axis field intensity and preserves phase continuity near the shadow boundary, in full agreement with the dual electromagnetic behavior predicted for PMC interfaces. Beyond its theoretical completeness, the proposed formulation provides a compact and computationally efficient framework for diffraction modeling and hybrid solver integration, offering practical applicability to magnetic coatings, low-RCS reflectors, and metasurface-based structures.
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    Food nationalism, price and fraud in imported agricultural product preference
    (Tarım Ekonomisi Derneği, 2025-11) Sönmezay, Mine; 409821
    Purpose: This study investigates how food nationalism, adulteration perception and perceived price shape Turkish consumers’ attitudes and purchase intentions toward imported agricultural foods. Design/methodology/approach: Using an online survey, data from 213 adults were analysed with partial least squares structural equation modelling (PLS-SEM). Findings: The strongest relationship in the model is that perceived price positively affects attitude towards imported products (β = 0.771, p < 0.001). Food nationalism variable significantly but weakly negatively affected attitude (β = –0.103, p = 0.023). No significant relationship was found between perception of adulteration and attitude (β = –0.060, p = 0.221). The effect of attitude on purchase intention is significant and negative (β = –0.377, p < 0.001). The purchase intention scale is reverse scored; therefore, a negative coefficient actually indicates a positive behavioral intention. The explanatory power of the model is high for attitude (R² = 0.65) and weak for purchase intention (R² = 0.142). Research limitations/Implications: Convenience sampling and online collection restrict generalisability; future studies should adopt probability sampling, broader demographics and mixed methods. Adding perceived quality, brand image and health concerns may enhance explanatory power. Social implications: Marketers should highlight quality rather than engage solely in price competition, while policymakers can bolster consumer welfare through price-advantage regulations. Originality/Value: By integrating food nationalism, adulteration perception and price perception into a single structural model, this research provides a holistic, empirically validated framework that advances understanding of imported-food choice drivers in an emerging economy.
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    The role of schooling in shaping the fishing footprint in Greece: evidence from an augmented ARDL approach
    (INIDEP, 2026-01) Karahan-Dursun, Pınar; Şengül, Serkan; Canbay, Şerif; 414023; 355807
    The fishing footprint, which reflects humanity’s demand on marine ecosystems and is closely linked to fisheries sustainability, serves as the main environmental indicator for marine resources. This study investigated the role of schooling as an indicator of human capital in shaping the fishing footprint in Greece over the period 1990-2022. The empirical analysis employed the Augmented ARDL (AARDL) approach, concentrating on the potential nonlinear relationship between human capital and environmental degradation in fishing grounds. The findings reveal the threshold effects of schooling: while lower levels of human capital increase environmental pressure, once a certain threshold is surpassed, human capital contributes to reducing environmental degradation in fisheries. Furthermore, the results validate the Environmental Kuznets Curve (EKC) and Environmental Phillips Curve (EPC) hypotheses in the context of fishing grounds.