WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653

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  • Article
    Solution Approaches for the Dynamic Naval Air Defense Planning Problem
    (Institute of Electrical and Electronics Engineers Inc., 2026) Arslan, C.; Karasakal, O.; Kirca, Ö.
    The naval air defense planning (NADP) problem entails the defense of a naval fleet against aerial threats. This complex and dynamic problem requires real-time decision-making and adaptation to evolving warfare environment. While our previous work addressed the static NADP problem by proposing a mathematical model and heuristic solutions for sensor allocation, engagement scheduling, and ship routing, this study extends to the dynamic NADP problem. Unlike the static version, which assumes complete knowledge of future threats, the dynamic NADP problem requires continuous updates and real-time adjustments to decisions as new threats emerge and situational parameters change. We present modifications in the mathematical formulation, which is based on a mixed-integer nonlinear programming (MINLP) model, alongside a comprehensive simulation structure. We employ heuristic solution approaches that utilize a combination of a genetic algorithm, construction of an engagement graph to solve the shortest path problem, and dynamic programming (DP) techniques. Computational experiments are conducted to evaluate the effectiveness of these methods in addressing the dynamic NADP problem. The study also explores machine learning models for threat prioritization, offering innovative solutions to the challenges posed by dynamic naval air defense scenarios. © 2013 IEEE.
  • Article
    Citation - WoS: 1
    Multiplicative Tempered Fractional Integrals in G-Calculus and Associated Hermite-Hadamard Inequalities
    (World Scientific Publ Co Pte Ltd, 2026) Lakhdari, Abdelghani; Saleh, Wedad; Budak, Huseyin; Meftah, Badreddine; Jarad, Fahd
    This paper introduces the first theory of tempered fractional integrals within the framework of G-calculus, a multiplicative non-Newtonian system for positive-valued functions with positive arguments. We begin by formulating the multiplicative Riemann-Liouville integral in its pure multiplicative form and extend it to include an exponential tempering parameter. A new multiplicative lambda-incomplete Gamma function is defined to characterize these operators. Furthermore, we introduce and analyze multiplicative convexity in G-calculus, along with novel multiplicative formulations of the classical midpoint and trapezoidal quadrature rules. We then establish the Hermite-Hadamard inequalities for GG-convex functions and derive two novel multiplicative integral identities, leading to midpoint- and trapezium-type bounds. Numerical examples with graphical illustrations, applications to quadrature rules, and connections to special means validate our results. The proposed framework fills a critical gap in non-Newtonian analysis and provides new tools for modeling scale-invariant phenomena in economics, biology, and signal processing.
  • Article
    On the Finite Delayed Fractional Differential Equation via the Weighted Riemann-Liouville Derivative of Variable Order
    (World Scientific Publ Co Pte Ltd, 2026) Jarad, Fahd; Abdeljawad, Thabet; Souid, Mohammed Said; Hallouz, Abdelhamid; Alqudah, Manar
    This study investigates the existence and uniqueness of solutions to initial value problems for nonlinear variable-order weighted fractional differential equations with finite delay. Building upon and generalizing prior constant-order fractional models, our approach employs fixed-point theory, specifically the Banach and Schauder fixed-point theorems, in suitable weighted function spaces to rigorously establish these fundamental results. We further demonstrate the applicability of our theoretical framework through illustrative examples. The findings contribute significantly to the mathematical understanding and modeling capabilities of complex systems exhibiting memory and hereditary properties governed by variable-order fractional dynamics.
  • Article
    Researcher as an Enigmatic Object in a Fieldwork on Addiction: Positionality within the Lacanian Context
    (Routledge Journals, Taylor & Francis Ltd, 2026) Canbolat, Fazilet
    How can positionality be understood beyond ego-based notions of identity? This article addresses this question by using Parker's Lacanian Discourse Analysis to explore positionality at the level of the subject, rather than the coherent researcher-self often assumed in reflexive accounts. The analysis draws on a text authored by the researcher that does not merely document interactions with gatekeepers during a one-year postdoctoral study on addiction among immigrants, but also incorporates the researcher's own reflexive statements, ethical and methodological considerations, and theoretical interpretations; accordingly, the researcher is treated as the sole participant. This type of analysis demonstrates how Lacanian Discourse Analysis enables an investigation of positionality that foregrounds division, misrecognition, and the influence of social and academic discourses, rather than personal identity alone. From a post-structuralist perspective, the article evaluates reflexivity and positionality as fluid, recursive, and contingent processes, arguing that reflexive writing necessarily stages the limits of self-knowledge rather than resolving them.
  • Article
    An Investigation of Discontinuities in Time-Dependent 2D and 3D Parabolic Partial Differential Equations Utilizing Collocation Methods: A Comparative Analysis of Complex Interface Problems
    (Springer Heidelberg, 2025) Faheem, Muhammad; Asif, Muhammad; Amin, Rohul; Haider, Nadeem; Jarad, Fahd
    Parabolic double interface problems have many applications in the fields such as materials science, fluid dynamics, and heat transfer. This paper presents a comparison of the Haar wavelet-based collocation method and two variants of radial basis function (RBF) method for solving 2D and 3D, linear as well as nonlinear, parabolic double interface problems. The two variants of RBF methods are the multiquadric RBF method and the integrated RBF method. For linear problems, the system of equations obtained from the integrated RBF method is solved using Moore-Penrose pseudoinverse. Error analysis is performed using L infinity\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$L_\infty $$\end{document} norm error and root mean square error, and the findings are discussed in detail. The methods are compared based on their accuracy and efficiency in solving different benchmark problems. The results show that both the Haar wavelet collocation method and the integrated RBF method perform better than the conventional RBF method in terms of accuracy.
  • Article
    A Class of Time-Fractional Dirac Type Operators
    (Pergamon-Elsevier Science Ltd, 2021) Baleanu, Dumitru; Restrepo, Joel E.; Suragan, Durvudkhan
    By using a Witt basis, a new class of time-fractional Dirac type operators with time-variable coefficients is introduced. These operators lead to considering a wide range of fractional Cauchy problems. Solutions of the considered general fractional Cauchy problems are given explicitly. The representations of the solutions can be used efficiently for analytic and computational purposes. We apply the obtained representation of a solution to recover a variable coefficient solution of an inverse fractional Cauchy problem. Some concrete examples are given to show the diversity of the obtained results. (c) 2020 Elsevier Ltd. All rights reserved.
  • Article
    Citation - WoS: 5
    On the Solution of a Parabolic PDE Involving a Gas Flow Through a Semi-Infinite Porous Medium
    (Amsterdam, 2021) Pop, Daniel N.; Vrinceanu, N.; Al-Omari, S.; Ouerfelli, N.; Baleanu, D.; Nisar, K. S.
    Taking as start point the parabolic partial differential equation with the respective initial and boundary conditions, the present research focuses onto the flow of a sample of waste-water derived from a standard/conventional dyeing process. In terms of a highly prioritized concern, meaning environment decontamination and protection, in order to remove the dyes from the waste waters, photocatalyses like ZnO or TiO2 nanoparticles were formulated, due to their high surface energy which makes them extremely reactive and attractive. According to the basics of ideal fluid, the key point is the gas flow through an ideal porous pipe consisting of nanoparticles bound one to each other, forming a porous matrix/pipe. The modeling of the gas flow through a porous media is quite valuable because of its importance in investigating the gas-solid processes. The present study is a valid contribution to the existing literature, by developing a nonstandard line method for the partial differential equation, in order to obtain a numerical solution of unsteady flow of gas through nano porous medium. Hence, the physical problem is modeled by a highly nonlinear ordinary differential equation detailed on a semi-finite domain and represents a guidance for several questions originating in the gas flow theory. The findings of this study offered a facile approach to improve an attractive issue related to materials science/chemistry, like synthesis of ZnO or TiO2 nanoparticles forming an ideal nano porous pipe with efficiency in industrial waste waters decontamination.
  • Article
    Citation - Scopus: 1
    Finite Bivariate Biorthogonal I-Konhauser Polynomials
    (Elsevier, 2026) Lekesiz, Esra Guldogan; Cekim, Bayram; Ozarslan, Mehmet Ali; Güldoğan Lekesi̇z, Esra
    In the present study, a finite set of biorthogonal polynomials in two variables, produced from Konhauser polynomials, is introduced. Some properties like Laplace transform, integral and operational representation, fractional calculus operators of this family are investigated. Also, we compute Fourier transform for this new set and discover a new family of finite biorthogonal functions with the help of Parseval's identity. Further, in order to have semigroup property, we modify this finite set by adding two new parameters and construct fractional calculus operators. Thus, integral equation and integral operator are obtained for the modified version.
  • Article
    Citation - WoS: 43
    On Fractional-Order Symmetric Oscillator With Offset-Boosting Control
    (Vilnius Univ Press, 2022) Xu, Changjin; Rahman, Mati Ur; Baleanu, Dumitru
    This article analyzes the dynamical evolution of a three-dimensional symmetric oscillator with a fractional Caputo operator. The dynamical properties of the considered model such as equilibria and its stability are also presented. The existence results and uniqueness of solutions for the suggested model are analyzed using the tools from fixed point theory. The symmetric oscillator is analyzed numerically and graphically with various fractional orders. It is observed that the fractional operator has a significant impact on the evolution of the oscillator dynamics showing that the system has a limit-cycle attractor. Offset-boosting control phenomena in the system are also studied with different orders and parameters.
  • Article
    Crack Propagation and Shear Band Evolution in Marginal AL-RE Metallic Glasses
    (Elsevier Ltd, 2025) Acun, Elif; Sun, Fan; Kalay, Ilkay; Berger, Marie-Helene; Kalay, Yunus Eren
    Aluminum-rare earth marginal metallic glasses (MMGs) exhibit unique devitrification behavior, with an exceptionally high density of face-centered cubic (fcc) Al nanocrystals after the first crystallization reaction. The origin of these highly populated fcc-Al nanocrystals has been linked to a possible medium-range order (MRO) that exists within the as-quenched MMGs. However, the formation and propagation of shear bands in these MRO containing marginally glassy metallic alloys have not been thoroughly investigated and remain an open question. In this respect, we have investigated the shear band propagation using in-situ tensile straining within a transmission electron microscope (TEM). The results reveal that deformation-induced nanocrystallization occurs within shear bands, with fcc-Al nanocrystals forming in the adiabatic heat-affected zone as the crack propagates. TEM analysis indicates that nanocrystals with an average size of 5 nm form at shear bands before final fracture, providing enhanced crack deflection and energy dissipation. In that sense, MRO within the amorphous structure is believed to act as precursors, enabling the rapid formation of these fcc-Al nanocrystals under mechanical loading. Additionally, it has been shown that MRO causes heterogeneous mechanical responses, leading to variations in shear resistance within the glassy matrix. These variations contribute to the redirection, branching, and blunting as they encounter MRO embedded regions with differing local stiffness and energy dissipation capacity. © 2025 Elsevier B.V., All rights reserved.