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Fen - Edebiyat Fakültesi

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Citation - WoS: 0
Citation - Scopus: 0
A 6-point subdivision scheme and its applications for the solution of 2nd order nonlinear singularly perturbed boundary value problems
(Amer inst Mathematical Sciences-aims, 2020) Mustafa, Ghulam; Baleanu, Dumitru; Baleanu, Dumitru; Ejaz, Syeda Tehmina; Anju, Kaweeta; Ahmadian, Ali; Salahshour, Soheil; Ferrara, Massimiliano; 56389; Matematik
In this paper, we first present a 6-point binary interpolating subdivision scheme (BISS) which produces a C-2 continuous curve and 4th order of approximation. Then as an application of the scheme, we develop an iterative algorithm for the solution of 2nd order nonlinear singularly perturbed boundary value problems (NSPBVP). The convergence of an iterative algorithm has also been presented. The 2nd order NSPBVP arising from combustion, chemical reactor theory, nuclear engineering, control theory, elasticity, and fluid mechanics can be solved by an iterative algorithm with 4th order of approximation.
Citation - WoS: 7
Citation - Scopus: 5
A Brief Overview and Survey of the Scientific Work by Feng Qi
(Mdpi, 2022) Agarwal, Ravi Prakash; Karapinar, Erdal; Kostic, Marko; Cao, Jian; Du, Wei-Shih; 19184
In the paper, the authors present a brief overview and survey of the scientific work by Chinese mathematician Feng Qi and his coauthors.
Citation - Scopus: 23
A Caputo-Fabrizio Fractional-Order Cholera Model And İts Sensitivity Analysis
(Mehmet Yavuz, 2023) Ahmed, I.; Jarad, Fahd; Akgül, A.; Jarad, F.; Kumam, P.; Nonlaopon, K.; 234808; Matematik
In recent years, the availability of advanced computational techniques has led to a growing emphasis on fractional-order derivatives. This development has enabled researchers to explore the intricate dynamics of various biological models by employing fractional-order derivatives instead of traditional integer-order derivatives. This paper proposes a Caputo-Fabrizio fractional-order cholera epidemic model. Fixed-point theorems are utilized to investigate the existence and uniqueness of solutions. A recent and effective numerical scheme is employed to demonstrate the model’s complex behaviors and highlight the advantages of fractional-order derivatives. Additionally, a sensitivity analysis is conducted to identify the most influential parameters. © 2023 by the authors.
Citation - WoS: 165
A central difference numerical scheme for fractional optimal control problems
(Sage Publications Ltd, 2009) Baleanu, Dumitru; Baleanu, Dumitru; Defterli, Ozlem; Defterli, Özlem; Agrawal, Om P.; 56389; 31401; Matematik
This paper presents a modified numerical scheme for a class of fractional optimal control problems where a fractional derivative (FD) is defined in the Riemann-Liouville sense. In this scheme, the entire time domain is divided into several sub-domains, and a FD at a time node point is approximated using a modified Grunwald-Letnikov approach. For the first-order derivative, the proposed modified Grunwald-Letnikov definition leads to a central difference scheme. When the approximations are substituted into the fractional optimal control equations, it leads to a set of algebraic equations which are solved using a direct numerical technique. Two examples, one time-invariant and the other time-variant, are considered to study the performance of the numerical scheme. Results show that 1) as the order of the derivative approaches an integer value, these formulations lead to solutions for the integer-order system, and 2) as the sizes of the sub-domains are reduced, the solutions converge. It is hoped that the present scheme would lead to stable numerical methods for fractional differential equations and optimal control problems.
Citation - WoS: 72
Citation - Scopus: 99
A Chebyshev spectral method based on operational matrix for fractional differential equations involving non-singular Mittag-Leffler kernel
(Springer, 2018) Baleanu, D.; Baleanu, Dumitru; Shiri, B.; Srivastava, H. M.; Al Qurashi, M.; 56389; Matematik
In this paper, we solve a system of fractional differential equations within a fractional derivative involving the Mittag-Leffler kernel by using the spectral methods. We apply the Chebyshev polynomials as a base and obtain the necessary operational matrix of fractional integral using the Clenshaw-Curtis formula. By applying the operational matrix, we obtain a system of linear algebraic equations. The approximate solution is computed by solving this system. The regularity of the solution investigated and a convergence analysis is provided. Numerical examples are provided to show the effectiveness and efficiency of the method.
Citation - WoS: 9
Citation - Scopus: 9
A class of fractal Hilbert-type inequalities obtained via Cantor-type spherical coordinates
(Wiley, 2021) Baleanu, Dumitru; Baleanu, Dumitru; Krnic, Mario; Vukovic, Predrag; 56389; Matematik
We present a class of higher dimensional Hilbert-type inequalities on a fractal set (Double-struck capital R+alpha n)k. The crucial step in establishing our results are higher dimensional spherical coordinates on a fractal space. Further, we impose the corresponding conditions under which the constants appearing in the established Hilbert-type inequalities are the best possible. As an application, our results are compared with the previous results known from the literature.
Citation - WoS: 4
Citation - Scopus: 4
A Class of Refinement Schemes With Two Shape Control Parameters
(Ieee-inst Electrical Electronics Engineers inc, 2020) Mustafa, Ghulam; Baleanu, Dumitru; Hameed, Rabia; Baleanu, Dumitru; Mahmood, Ayesha; 56389; Matematik
A subdivision scheme defines a smooth curve or surface as the limit of a sequence of successive refinements of given polygon or mesh. These schemes take polygons or meshes as inputs and produce smooth curves or surfaces as outputs. In this paper, a class of combine refinement schemes with two shape control parameters is presented. These even and odd rules of these schemes have complexity three and four respectively. The even rule is designed to modify the vertices of the given polygon, whereas the odd rule is designed to insert a new point between every edge of the given polygon. These schemes can produce high order of continuous shapes than existing combine binary and ternary family of schemes. It has been observed that the schemes have interpolating and approximating behaviors depending on the values of parameters. These schemes have an interproximate behavior in the case of non-uniform setting of the parameters. These schemes can be considered as the generalized version of some of the interpolating and B-spline schemes. The theoretical as well as the numerical and graphical analysis of the shapes produced by these schemes are also presented.
Citation - WoS: 17
Citation - Scopus: 19
A comprehensive analysis of the stochastic fractal–fractional tuberculosis model via Mittag-Leffler kernel and white noise
(Elsevier, 2022) Rashid, Saima; Jarad, Fahd; Iqbal, Muhammad Kashif; Alshehri, Ahmed M.; Ashraf, Rehana; Jarad, Fahd; 234808; Matematik
In this research, we develop a stochastic framework for analysing tuberculosis (TB) evolution that includes new-born immunization via the fractal-fractional (F-F) derivative in the Atangana-Baleanu sense. The population is divided into four groups by this system: susceptibility S(xi), infectious I(xi), immunized infants V(xi), and restored R(xi). The stochastic technique is used to describe and assess the invariant region, basic reproduction number, and local stability for disease-free equilibrium. This strategy has significant modelling difficulties since it ignores the unpredictability of the system phenomena. To prevent such problems, we convert the deterministic strategy to a randomized one, which seems recognized to have a vital influence by adding an element of authenticity and fractional approach. Owing to the model intricacies, we established the existence-uniqueness of the model and the extinction of infection was carried out. We conducted a number of experimental tests using the F-F derivative approach and obtained some intriguing modelling findings in terms of (i) varying fractional-order (phi) and fixing fractal-dimension (omega), (ii) varying omega and fixing phi, and (iii) varying both phi and omega, indicating that a combination of such a scheme can enhance infant vaccination and adequate intervention of infectious patients can give a significant boost.
Citation - WoS: 11
Citation - Scopus: 11
A Computational Approach Based On The Fractional Euler Functions And Chebyshev Cardinal Functions For Distributed-Order Time Fractional 2D Diffusion Equation
(Elsevier, 2023) Heydari, M. H.; Hosseininia, M.; Baleanu, D.; 56389
In this paper, the distributed-order time fractional diffusion equation is introduced and studied. The Caputo fractional derivative is utilized to define this distributed-order fractional derivative. A hybrid approach based on the fractional Euler functions and 2D Chebyshev cardinal functions is proposed to derive a numerical solution for the problem under consideration. It should be noted that the Chebyshev cardinal functions process many useful properties, such as orthogonal-ity, cardinality and spectral accuracy. To construct the hybrid method, fractional derivative oper-ational matrix of the fractional Euler functions and partial derivatives operational matrices of the 2D Chebyshev cardinal functions are obtained. Using the obtained operational matrices and the Gauss-Legendre quadrature formula as well as the collocation approach, an algebraic system of equations is derived instead of the main problem that can be solved easily. The accuracy of the approach is tested numerically by solving three examples. The reported results confirm that the established hybrid scheme is highly accurate in providing acceptable results.(c) 2023 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/ 4.0/).
Citation - WoS: 10
Citation - Scopus: 9
A computational study of a stochastic fractal-fractional hepatitis B virus infection incorporating delayed immune reactions via the exponential decay
(Amer inst Mathematical Sciences-aims, 2022) Al Qurashi, Maysaa; Jarad, Fahd; Rashid, Saima; Jarad, Fahd; 234808; Matematik
Recently, researchers have become interested in modelling, monitoring, and treatment of hepatitis B virus infection. Understanding the various connections between pathogens, immune systems, and general liver function is crucial. In this study, we propose a higher-order stochastically modified delay differential model for the evolution of hepatitis B virus transmission involving defensive cells. Taking into account environmental stimuli and ambiguities, we presented numerical solutions of the fractal-fractional hepatitis B virus model based on the exponential decay kernel that reviewed the hepatitis B virus immune system involving cytotoxic T lymphocyte immunological mechanisms. Furthermore, qualitative aspects of the system are analyzed such as the existence-uniqueness of the non-negative solution, where the infection endures stochastically as a result of the solution evolving within the predetermined system's equilibrium state. In certain settings, infection-free can be determined, where the illness settles down tremendously with unit probability. To predict the viability of the fractal-fractional derivative outcomes, a novel numerical approach is used, resulting in several remarkable modelling results, including a change in fractional-order delta with constant fractal-dimension pi, delta with changing pi, and delta with changing both delta and pi. White noise concentration has a significant impact on how bacterial infections are treated.
Citation - WoS: 20
Citation - Scopus: 24
A coupled system of generalized Sturm-Liouville problems and Langevin fractional differential equations in the framework of nonlocal and nonsingular derivatives
(Springer, 2020) Baleanu, D.; Baleanu, Dumitru; Alzabut, J.; Jonnalagadda, J. M.; Adjabi, Y.; Matar, M. M.; 56389; Matematik
In this paper, we study a coupled system of generalized Sturm-Liouville problems and Langevin fractional differential equations described by Atangana-Baleanu-Caputo (ABC for short) derivatives whose formulations are based on the notable Mittag-Leffler kernel. Prior to the main results, the equivalence of the coupled system to a nonlinear system of integral equations is proved. Once that has been done, we show in detail the existence-uniqueness and Ulam stability by the aid of fixed point theorems. Further, the continuous dependence of the solutions is extensively discussed. Some examples are given to illustrate the obtained results.
A Critical Review of the Joker Movie in the Context of Mahler's Separation-İndividuatin theory and PTSD
(2021) Güven, Ayşenur; Işık, Selin; Oya, Sera; Yaşar, Nuray; Topcu Bulut, Merve
Bu çalışmada Mahler’in ayrılma-bireyleşme kuramı çerçevesinde Joker filmindeki Arthur Fleck karakterinin gelişim evreleri hakkında çıkarımlar yapılması, ilk 36 aylık deneyimlerinin Arthur’un duygu, düşünce ve kişilik gelişimindeki etkilerinin incelenmesi amaçlanmıştır. Mahler’in kuramına göre bireyin ilk altı ayı normal otistik ve normal ortakyaşamsal olmak üzere, birbirinin devamı ve tamamlayıcısı niteliğindeki iki kritik evreden oluşmaktadır. Devamında ise farklılaşma, alıştırma, yeniden yakınlaşma ve bireyliğin pekişmesi ve coşkusal nesne sürekliliğinin başlangıcı olmak üzere dört farklı altevreden oluşan ayrılma-bireyleşme süreci gelmektedir. Kişilik oluşumu sürecinde bu altevreler büyük önem taşımaktadır. Arthur’un narsistik ve madde kötüye kullanım tanısı almış olan annesi ile ilişkisi, baba kavramının eksikliği, çevresiyle olan etkileşimi ve toplum içinde görünür olma arzusu üzerinde durulmuştur. Çocukluk çağında istismar ve ihmale uğrayan, yetişkinlik çağında ise sistematik olarak psikolojik şiddete maruz kalmaya devam eden Arthur'un örseleyici yaşam öyküsü kimlik oluşumunu, sosyal uyumunu, kişilik gelişimini olumsuz etkilemiş ve örselenme sonrası gerginlik bozukluğu (ÖSGB) belirtilerinin oluşmasına yol açmıştır. Bahsedilen bilgiler ışığında Arthur Fleck karakteri, DSM-5 örselenme sonrası gerginlik bozukluğu tanı kriterlerinden faydalanılarak Mahler’in ayrılma-bireyleşme kuramı çerçevesinde incelenmiştir.
Citation - WoS: 4
Citation - Scopus: 4
A Decomposıtıon Algorıthm Coupled Wıth Operatıonal Matrıces Approach Wıth Applıcatıons To Fractıonal Dıfferentıal Equatıons
(Vinca inst Nuclear Sci, 2021) Talib, Imran; Baleanu, Dumitru; Alam, Md Nur; Baleanu, Dumitru; Zaidi, Danish; 56389; Matematik
In this article, we solve numerically the linear and non-linear fractional initial value problems of multiple orders by developing a numerical method that is based on the decomposition algorithm coupled with the operational matrices approach. By means of this, the fractional initial value problems of multiple orders are decomposed into a system of fractional initial value problems which are then solved by using the operational matrices approach. The efficiency and advantage of the developed numerical method are highlighted by comparing the results obtained otherwise in the literature. The construction of the new derivative operational matrix of fractional legendre function vectors in the Caputo sense is also a part of this research. As applications, we solve several fractional initial value problems of multiple orders. The numerical results are displayed in tables and plots.
Citation - WoS: 37
Citation - Scopus: 39
A delayed plant disease model with Caputo fractional derivatives
(Springer, 2022) Kumar, Pushpendra; Baleanu, Dumitru; Baleanu, Dumitru; Erturk, Vedat Suat; Inc, Mustafa; Govindaraj, V; 56389; Matematik
We analyze a time-delay Caputo-type fractional mathematical model containing the infection rate of Beddington-DeAngelis functional response to study the structure of a vector-borne plant epidemic. We prove the unique global solution existence for the given delay mathematical model by using fixed point results. We use the Adams-Bashforth-Moulton P-C algorithm for solving the given dynamical model. We give a number of graphical interpretations of the proposed solution. A number of novel results are demonstrated from the given practical and theoretical observations. By using 3-D plots we observe the variations in the flatness of our plots when the fractional order varies. The role of time delay on the proposed plant disease dynamics and the effects of infection rate in the population of susceptible and infectious classes are investigated. The main motivation of this research study is examining the dynamics of the vector-borne epidemic in the sense of fractional derivatives under memory effects. This study is an example of how the fractional derivatives are useful in plant epidemiology. The application of Caputo derivative with equal dimensionality includes the memory in the model, which is the main novelty of this study.
Citation - WoS: 8
Citation - Scopus: 12
A detailed study on a new (2+1)-dimensional mKdV equation involving the Caputo-Fabrizio time-fractional derivative
(Springer, 2020) Hosseini, K.; Baleanu, Dumitru; Ilie, M.; Mirzazadeh, M.; Baleanu, D.; 56389; Matematik
The present article aims to present a comprehensive study on a nonlinear time-fractional model involving the Caputo-Fabrizio (CF) derivative. More explicitly, a new (2+1)-dimensional mKdV (2D-mKdV) equation involving the Caputo-Fabrizio time-fractional derivative is considered and an analytic approximation for it is retrieved through a systematic technique, called the homotopy analysis transform (HAT) method. Furthermore, after proving the Lipschitz condition for the kernel psi (x,y,t;u), the fixed-point theorem is formally utilized to demonstrate the existence and uniqueness of the solution of the new 2D-mKdV equation involving the CF time-fractional derivative. A detailed study finally is carried out to examine the effect of the Caputo-Fabrizio operator on the dynamics of the obtained analytic approximation.
Citation - WoS: 19
Citation - Scopus: 22
A discussion on a generalized Geraghty multi-valued mappings and applications
(Springer, 2020) Afshari, Hojjat; Karapınar, Erdal; Atapour, Maryam; Karapinar, Erdal; 19184; Matematik
This research intends to investigate the existence results for both coincidence points and common fixed point of generalized Geraghty multi-valued mappings endowed with a directed graph. The proven results are supported by an example. We also consider fractional integral equations as an application.
Citation - WoS: 5
Citation - Scopus: 6
A discussion on a pata type contraction via iterate at a point
(Univ Nis, Fac Sci Math, 2020) Karapinar, Erdal; Karapınar, Erdal; Fulga, Andreea; Rakocevic, Vladimir; 19184; Matematik
In this paper, we introduce the notion of Pata type contraction at a point in the context of a complete metric space. We observe that such contractions possesses unique fixed point without continuity assumption on the given mapping. Thus, is extended the original results of Pata. We also provide an example to illustrate its validity.
Citation - WoS: 7
Citation - Scopus: 10
A Discussion On Random Meir-Keeler Contractions
(Mdpi, 2020) Li, Cheng-Yen; Karapınar, Erdal; Karapinar, Erdal; Chen, Chi-Ming; 19184; Matematik
The aim of this paper is to enrich random fixed point theory, which is one of the cornerstones of probabilistic functional analysis. In this paper, we introduce the notions of random, comparable MT-gamma contraction and random, comparable Meir-Keeler contraction in the framework of complete random metric spaces. We investigate the existence of a random fixed point for these contractions. We express illustrative examples to support the presented results.
Citation - WoS: 2
Citation - Scopus: 2
A discussion on the coincidence quasi-best proximity points
(Univ Nis, Fac Sci Math, 2021) Fouladi, Farhad; Karapınar, Erdal; Abkar, Ali; Karapinar, Erdal; 19184; Matematik
In this paper, we first introduce a new class of the pointwise cyclic-noncyclic proximal contraction pairs. Then we consider the coincidence quasi-best proximity point problem for this class. Finally, we study the coincidence quasi-best proximity points of weak cyclic-noncyclic Kannan contraction pairs. We consider an example to indicate the validity of the main result.
Citation - WoS: 9
Citation - Scopus: 10
A Discussion On the Existence of Best Proximity Points That Belong to the Zero Set
(Mdpi, 2020) Karapinar, Erdal; Karapınar, Erdal; Abbas, Mujahid; Farooq, Sadia; 19184; Matematik
In this paper, we investigate the existence of best proximity points that belong to the zero set for the alpha p -admissible weak (F,phi) -proximal contraction in the setting of M-metric spaces. For this purpose, we establish phi -best proximity point results for such mappings in the setting of a complete M-metric space. Some examples are also presented to support the concepts and results proved herein. Our results extend, improve and generalize several comparable results on the topic in the related literature.