Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Mathematical Analysis and Numerical Simulations of Ternary Hybrid Nanoparticles Using Eyring Prandtl Model(Engineered Science Publisher, 2026) Abdalla, Bahaaeldin; Zeb, Hussan; Jarad, Fahd; Oweidi, Khalid Fanoukh Al; Ali, Zeeshan; Abdeljawad, Thabet; Shah, KamalArticle Widths and Entropy of Sets of Smooth Functions on Compact Homogeneous Manifolds(Tubitak, 2021) LEVESLEY, Jeremy; KUSHPEL, Alexander; Taş, KenanWe develop a general method to calculate entropy and n-widths of sets of smooth functions on an arbitrary compact homogeneous Riemannian manifold Md . Our method is essentially based on a detailed study of geometric characteristics of norms induced by subspaces of harmonics on Md . This approach has been developed in the cycle of works [1, 2, 10–19]. The method’s possibilities are not confined to the statements proved but can be applied in studying more general problems. As an application, we establish sharp orders of entropy and n-widths of Sobolev’s classes Wγ p ( Md ) and their generalisations in Lq ( Md ) for any 1 < p, q < ∞. In the case p, q = 1, ∞ sharp in the power scale estimates are presented.Article The Role and Importance of Human Capital in Exports and Growth: The Case of Türkiye(Inderscience Publishers, 2026) Temiz, Dilek; Gökmen, AytaçArticle Sustainable Development Solutions Network (SDSN) Reports Between 2018 and 2023: Malmquist Index Analysis for the Performance of OECD Countries(Wiley, 2026) Kalemci, R. Arzu; Unsal, Mehmet Guray; Alp, Ihsan; Celik, Busra Agan; Dalkilic, Altay Ogulcan; Agan Celik, BusraIn 2015, the United Nations (UN) adopted the 17 Sustainable Development Goals (SDGs), calling for urgent action to end poverty, reduce inequality, and secure a sustainable future. Within this global agenda, the commitment of the Organization for Economic Co-operation and Development (OECD) is particularly significant given its institutional capacity and international influence. This study examines Sustainable Development Solutions Network (SDSN) reports for 2018-2023 using the Malmquist Productivity Index (MPI) as an alternative performance measurement tool. The MPI allows assessment of annual changes in total factor productivity and efficiency differences across OECD members. Rather than directly measuring absolute progress toward the SDGs, the analysis evaluates relative efficiency dynamics among countries in transforming sustainability-related indicators over time. The results provide comparative insights into how OECD countries improve or deteriorate in their relative sustainability performance within the observed period. The results show that OECD countries display uneven progress, with some improving while others stagnate or decline, and reveal persistent disparities in efficiency and productivity. By providing a dynamic and comparative evaluation, the study contributes to quantitative SDG monitoring and offers insights for policymakers seeking to enhance sustainable development strategies.Article Simheuristic Framework for Optimizing Urban Mobility at Signalized Roundabouts(DAAAM International Vienna, 2026) Gokce, M. A.; Qadri, S. S. S. M.; Oner, E.Managing high traffic volumes and traffic congestion at signalized intersections remains a critical urban challenge. Appropriate traffic signal timing (TST) and phase sequencing are essential for ensuring smooth traffic flow. This study presents a microscopic simulation-based heuristic optimization (Simheuristic) framework using the Genetic Algorithm (GA) for optimizing the TST of Four-Legged Two-stops Signalized Roundabouts (FLTSR). The framework is tested using the actual traffic flow through a microscopic simulation model developed in Simulation for Urban Mobility (SUMO). Within this framework, the integrated GA searches for the green TSTs to minimize vehicular queue lengths, while SUMO is used to evaluate those timings. Additionally, four different phase sequence settings are evaluated to find the efficient configuration. The proposed approach is benchmarked against Webster's method and the existing TST plan. In the best-case scenario, the proposed framework improves vehicular flow by mitigating the average time loss, average waiting time, and the average number of vehicles in a queue at the FLTSR up to 35.83 %, 51.91 %, and 50.97 %, respectively, compared to the current setting. (Received in November 2025, accepted in January 2026. This paper was with the authors 1 month for 1 revision.)Article Revealing Fractional Effects in an Asymmetric Two-Dimensional Oscillator through Variational Mechanics(SAGE Publications Ltd, 2026) Baleanu, Dumitru; Defterli, Ozlem; Asad, Jihad; Jajarmi, Amin; AlShaikh Mohammad, Noorhan F.The present study is an application of a generalized Lagrangian-Hamiltonian approach to the analysis of an asymmetric two-dimensional harmonic oscillator with the use of the Caputo fractional derivative. Fractional Euler-Lagrange and Hamiltonian equations were systematically developed and then solved numerically using a predictor-corrector version of the Adams-Bashforth-Moulton method. The results show that decreasing the value of the fractional order (alpha) generates a form of memory-based damping within the system that transforms the classical closed orbits of phase space into spiral inward trajectories and causes the total energy of the system to decrease according to a power law, regardless of whether there are any dissipative forces in the system. It was demonstrated that both the degree of coupling and the degree of asymmetry can cause the system to lose energy at different rates and to have different amounts of attenuation in each direction. It was also demonstrated that the model provides a smooth transition to classical conservative behavior as alpha approaches unity, which confirms the physical validity of this representation. This demonstrates that fractional variational mechanics provides a consistent and physically meaningful way to describe the transition from conservative to dissipative behavior for coupled oscillating systems that are governed by memory and non-local effects.Article Finite Biorthogonal Polynomials Suggested by the Finite Orthogonal Polynomials Mnp,Qx(Wiley, 2026) Guldogan Lekesiz, EsraConstructing a biorthogonal structure from scratch, that is, defining a biorthogonal pair is quite tough. Because here the orthogonality must be established between two different sets. There are four known univariate biorthogonal polynomial sets, suggested by Laguerre, Jacobi, Hermite and Szeg & odblac;-Hermite polynomials, in the literature. In this paper, we derive for the first time a pair of finite univariate biorthogonal polynomials suggested by the finite univariate orthogonal polynomials . The corresponding biorthogonality relation and some useful relations and properties, including differential equation and generating function, are presented. Further, a new family of finite biorthogonal functions is obtained using Fourier transform and Parseval identity. In addition, we compute the Laplace transform and fractional calculus operators for the new biorthogonal polynomial set .Article Experimental Investigation of Granular Soil and Clay Interfaces with Direct Shear Tests(MDPI, 2026) Ozturk, Sevki; Ergun, Mehmet UfukThis study experimentally investigates the shear strength behavior of interfaces formed between granular soils and clay under drained conditions, with particular emphasis on peak-to-residual strength evolution. Large and small-scale direct shear tests were performed on clay, granular soils (sand and gravel), and their interfaces, and shearing was continued to large displacements to reliably capture residual behavior. Unlike most previous studies that focus on soil mixtures, this study explicitly quantifies interface-specific shear strength parameters and highlights their distinct mechanical response. The results show that while interface cohesion remains comparable to that of clay, the interface friction angle is consistently higher. Specifically, under residual conditions, the friction angle of the clay (12.9 degrees) increased to 16.4 degrees for the sand-clay interface and to 19.8 degrees for the gravel-clay interface. These findings demonstrate that adopting clay residual parameters for granular soil-clay interfaces may be overly conservative and that interface-specific residual friction angles should be considered in stability analyses of slopes and earth structures.Article Energy Intensity in CIS Economies: Insights into Convergence with OECD Benchmarks(Savez Ekonomista Vojvodine, 2026) Baskaraagac, Nermin YasarThis study evaluates energy intensity convergence in Commonwealth of Independent States (CIS) economies in comparison to the OECD average from 2000 to 2019, utilising beta-convergence and sigma-convergence analyses based on conventional unit root analysis alongside the KSS stationarity approach, which accounts for data nonlinearities, and the Phillips-Sul club convergence procedure. The results indicate that most CIS countries did not achieve energy intensity convergence during the period under review. Furthermore, while the Phillips-Sul test classifies all studied countries, including the OECD-20, into a single convergence club, it only presents weak evidence of significant convergence. This limited convergence is likely hindered by the continued presence of Soviet-era manufacturing infrastructure in many CIS economies. From a policy perspective, the development of comprehensive economic frameworks that incorporate legal, institutional, technical, and financial reforms, supported by targeted investments in research, cutting-edge technologies, and updated standards, is essential to significantly boost energy efficiency and effectively address challenges on both the supply and demand sides.Article An Investigation of Atmospheric Icing Effects on Wind Turbine Blade Aerodynamics and Power Output: A Case Study of the NREL 5 MW Turbine(MDPI, 2026) Ozturk, Berkay; Kocak, EyupThis study presents a numerical investigation of the effects of atmospheric icing on the aerodynamic performance and power output of the NREL 5 MW reference wind turbine. In cold climate regions, ice accretion on wind turbine blades significantly alters the airfoil geometry, leading to aerodynamic degradation characterized by increased drag, reduced lift, and substantial power losses. Understanding these effects is therefore essential for reliable performance prediction and efficient turbine operation under icing conditions. To address this problem, numerical simulations were conducted on six representative blade sections using the FENSAP-ICE framework, which integrates flow field calculations, droplet transport, and ice accretion modeling within a unified computational environment. The analyses were performed under different atmospheric icing conditions, considering liquid water content values of 0.22 g/m3 and 0.50 g/m3 and ambient temperatures of -2.5 degrees C and -10 degrees C. The median volumetric diameter was fixed at 20 & micro;m, and the icing duration was set to one hour for all cases, allowing for both glaze and rime ice formations to be systematically examined. The results reveal that ice accretion becomes increasingly pronounced toward the blade tip, mainly due to higher relative velocities and increased collection efficiency in the outer sections. Glaze icing conditions produce irregular horn-shaped ice formations and lead to severe aerodynamic degradation, whereas rime ice forms more compact structures near the leading edge and results in comparatively lower performance losses. The degraded aerodynamic coefficients obtained from the iced airfoils were subsequently incorporated into BEM-based power calculations, indicating that total power losses can reach up to 40% under severe icing conditions, with the outer blade sections contributing most significantly to this reduction. Furthermore, an economic assessment based on annual energy losses highlights the substantial impact of atmospheric icing on wind turbine performance and operational costs.
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