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Rough Approximations Based On Different Topologies Via Ideals, Ayşegül Çaksu Güler, Esra Dalan Yildirim, Oya Özbakir
Rough Approximations Based On Different Topologies Via Ideals, Ayşegül Çaksu Güler, Esra Dalan Yildirim, Oya Özbakir
Turkish Journal of Mathematics
In this paper, we generalize the notations of rough sets based on the topological space. Firstly, we produce various topologies by using the concept of ideal, $C_j$-neighbourhoods and $P_j$-neighbourhoods. When we compare these topologies with previous topologies, we see that these topologies are more general. Then we introduce new methods to find the approximations by using these generated topologies. When we compare these methods with the previous methods, we see that these methods are more accurate.
Small Genus-$4$ Lefschetz Fibrations On Simply-Connected $4$-Manifolds, Tüli̇n Altunöz
Small Genus-$4$ Lefschetz Fibrations On Simply-Connected $4$-Manifolds, Tüli̇n Altunöz
Turkish Journal of Mathematics
We consider simply connected $4$-manifolds admitting Lefschetz fibrations over the $2$-sphere. We explicitly construct nonhyperelliptic and hyperelliptic Lefschetz fibrations of genus $4$ on simply-connected $4$-manifolds which are exotic symplectic $4$-manifolds in the homeomorphism classes of $\mathbb{C} P^{2}\#8\overline{\mathbb{C} P^{2}}$ and $\mathbb{C} P^{2}\#9\overline{\mathbb{C} P^{2}}$, respectively. From these, we provide upper bounds for the minimal number of singular fibers of such fibrations. In addition, we prove that this number is equal to $18$ for $g=3$ when such fibrations are hyperelliptic. Moreover, we discuss these numbers for higher genera.
The Integer-Antimagic Spectra Of A Disjoint Union Of Hamiltonian Graphs, Uğur Odabaşi, Dan Roberts, Richard M. Low
The Integer-Antimagic Spectra Of A Disjoint Union Of Hamiltonian Graphs, Uğur Odabaşi, Dan Roberts, Richard M. Low
Turkish Journal of Mathematics
Let $A$ be a nontrivial abelian group. A simple graph $G = (V, E)$ is $A$-antimagic, if there exists an edge labeling $f: E(G) \to A \backslash \{0\}$ such that the induced vertex labeling $f^+(v)=\sum_{uv\in E(G)} f(uv)$ is a one-to-one map. The {integer-antimagic spectrum} of a graph $G$ is the set IAM$(G) = \{k: G {is} \mathbb{Z}_k{-antimagic and } k \geq 2\}$. In this paper, we determine the integer-antimagic spectra for a disjoint union of Hamiltonian graphs.
An Alternative Method For Spp With Full Rank (2,1)-Block Matrix And Nonzero Right-Hand Side Vector, Gül Karaduman, Mei Yang
An Alternative Method For Spp With Full Rank (2,1)-Block Matrix And Nonzero Right-Hand Side Vector, Gül Karaduman, Mei Yang
Turkish Journal of Mathematics
We propose an alternative method to solve large linear saddle point problems arising from computational sciences and engineering such as finite element approximations to Stokes problems, image reconstructions, tomography, genetics, statistics, and model order reductions for dynamical systems. Such problems have large sparse 2-by-2 block structure coefficient matrices with zero (2,2)-block matrix. A new technique is presented to solve saddle point problems with full row rank (2,1)-block matrix and nonzero right-hand side vector. By constructing a projection matrix and transforming the original problem into a least squares problem, a new reduced least squares problem is solved via the well-known iterative …
Quasilinear Systems With Unpredictable Relay Perturbations, Mehmet Onur Fen, Fatma Fen
Quasilinear Systems With Unpredictable Relay Perturbations, Mehmet Onur Fen, Fatma Fen
Turkish Journal of Mathematics
It is rigorously proven under certain assumptions that a quasilinear system with discontinuous right-hand side possesses a unique unpredictable solution. The discontinuous perturbation function on the right-hand side is defined by means of an unpredictable sequence. A Gronwall-Coppel type inequality is utilized to achieve the main result, and the stability of the unpredictable solution is discussed. Examples with exponentially asymptotically stable and unstable unpredictable solutions are provided.
Study Of The $\Phi$-Generalized Type $K$-Fractional Integrals Or Derivatives And Some Of Their Properties, Mustafa Aydin, Nazim I. Mahmudov
Study Of The $\Phi$-Generalized Type $K$-Fractional Integrals Or Derivatives And Some Of Their Properties, Mustafa Aydin, Nazim I. Mahmudov
Turkish Journal of Mathematics
A novel fractional integral in the sense of Riemann-Liouville integral and two new fractional derivatives in the sense of Riemann-Liouville derivative and Caputo derivative with respect to another function and two parameters are introduced. Some significant properties of them are presented like semigroup property, inverse property, etc. The solution of the Cauchy-type problem for the nonhomogenous linear differential equation with the $\phi$-generalized Caputo $k$-fractional derivative is given by using the method of successive approximation.
Univalence Criteria For Analytic Functions Obtained Using Fuzzydifferential Subordinations, Georgia Irina Oros
Univalence Criteria For Analytic Functions Obtained Using Fuzzydifferential Subordinations, Georgia Irina Oros
Turkish Journal of Mathematics
Ever since Lotfi A. Zadeh published the paper "Fuzzy Sets" in 1965 setting the basis of a new theory named fuzzy sets theory, many scientists have developed this theory and its applications. Mathematicians were especially interested in extending classical mathematical results in the fuzzy context. Such an extension was also done relating fuzzy sets theory and geometric theory of analytic functions. The study begun in 2011 has many interesting published outcomes and the present paper follows the line of the previous research in the field. The aim of the paper is to give some references related to the connections already …
Induced Polynomial Structures On Generalized Geometry, Fernando Etayo, Pablo Gomez Nicolas, Rafael Santamaria
Induced Polynomial Structures On Generalized Geometry, Fernando Etayo, Pablo Gomez Nicolas, Rafael Santamaria
Turkish Journal of Mathematics
In this paper, we study different geometric structures that can be defined as section endomorphisms of the generalized tangent bundle $\mathbb TM := TM\oplus T^*M\to M$. This vector bundle admits some structures that arise canonically and other that can be induced from geometric structures defined on the manifold. We comment some well-known examples and present new structures, focusing on the polynomial structures that can be induced in the generalized tangent bundle.
On Slack $2$-Geodesic Convex Set And Geodesic $E$-Pseudoconvex Function With Application, Akhlad Iqbal, Praveen Kumar, Izhar Ahmad
On Slack $2$-Geodesic Convex Set And Geodesic $E$-Pseudoconvex Function With Application, Akhlad Iqbal, Praveen Kumar, Izhar Ahmad
Turkish Journal of Mathematics
We introduce a new class of sets named, slack $2$-geodesic convex set on Riemannian manifolds and verify by a nontrivial example. We define a geodesic $E$-pseudoconvex function with a suitable example. Some properties of geodesic $E$-quasiconvex function are discussed. We establish some relationships between slack $2$-geodesic convex set, geodesic $E$-pseudoconvex function and geodesic $E$-quasiconvex function. Moreover, an application of geodesic $E$-quasiconvex function to a nonlinear programming problem is also presented.
Formal Categorical Reasoning, Burak Eki̇ci̇
Formal Categorical Reasoning, Burak Eki̇ci̇
Turkish Journal of Mathematics
In this paper, we present a category theory library developed in the proof assistant Coq. We discuss the design principles of the library in comparison with those existing out there. To explicitly demonstrate the utility of the library, we conclude with a case study in which a Coq formalized soundness proof of the intuitionistic propositional logic within a category theoretical settings is examined.
Capelli Identities On Algebras With Involution Or Graded Involution, Francesca Saviella Benanti, Angela Valenti
Capelli Identities On Algebras With Involution Or Graded Involution, Francesca Saviella Benanti, Angela Valenti
Turkish Journal of Mathematics
We present recent results about Capelli polynomials with involution or graded involution and their asymptotics. In the associative case, the asymptotic equality between the codimensions of the $T$-ideal generated by the Capelli polynomial of rank $k^2+1$ and the codimensions of the matrix algebra $M_k(F)$ was proved. This result was extended to superalgebras. Recently, similar results have been determined by the authors in the case of algebras with involution and superalgebras with graded involution.
Computing Forgotten Topological Index Of Zero-Divisor Graphs Of Commutative Rings, Ari̇f Gürsoy, Necla Kircali Gürsoy, Alper Ülker
Computing Forgotten Topological Index Of Zero-Divisor Graphs Of Commutative Rings, Ari̇f Gürsoy, Necla Kircali Gürsoy, Alper Ülker
Turkish Journal of Mathematics
The main objective of this paper is to calculate the forgotten topological index of the zero-divisor graph of $\mathbb{Z}_n$. Let $p$, $q$ and $r$ be distinct prime numbers. We calculate the forgotten topological index of the ring $\Gamma(\mathbb{Z}_n)$ where $n=p^\alpha, pq, p^2q, p^2q^2, pqr$. Also, we study the forgotten topological index of the product of rings of integers modulo $n$. We construct a polynomial algorithm to compute the forgotten topological index of $\Gamma(\mathbb{Z}_n)$.
A New Approach To Word Standardization And Some Of Its Applications, Wesam Talab
A New Approach To Word Standardization And Some Of Its Applications, Wesam Talab
Turkish Journal of Mathematics
In this article, we study word standardization in comparison to Young tableau standardization. We count the number of words (respectively Young tableau) standardized to a given permutation (respectively to a given standard Young tableau). We prove that both rectification and standardization applications commute and show that the standardization commutes with the insertion of Robinson--Schensted. We show that the standardizations of Knuth-equivalent two words are also Knuth equivalent. Finally, using word standardization we establish a proof for the following well-known equality: $$ \forall l \in \left\lbrace 0,1,\ldots,n-1\right\rbrace ,~~\left \langle {n\atop l} \right \rangle=d_{n,l}=a_{n,l}= \sum_{0\leq k \leq l}(-1)^k { n+1 \choose k …
Nilpotent Varieties And Metabelian Varieties, Angela Valenti, Sergey Mishchenko
Nilpotent Varieties And Metabelian Varieties, Angela Valenti, Sergey Mishchenko
Turkish Journal of Mathematics
We deal with varieties of nonassociative algebras having polynomial growth of codimensions. We describe some results obtained in recent years in the class of left nilpotent algebras of index two. Recently the authors established a correspondence between the growth rates for left nilpotent algebras of index two and the growth rates for commutative or anticommutative metabelian algebras that allows to transfer the results concerning varieties of left nilpotent algebras of index two to varieties of commutative or anticommutative metabelian algebras.
Analyzing Bifurcation, Stability, And Chaos Control For A Discrete-Time Prey-Predator Model With Allee Effect, Fi̇gen Kangalgi̇l, Ni̇lüfer Topsakal, Ni̇hal Öztürk
Analyzing Bifurcation, Stability, And Chaos Control For A Discrete-Time Prey-Predator Model With Allee Effect, Fi̇gen Kangalgi̇l, Ni̇lüfer Topsakal, Ni̇hal Öztürk
Turkish Journal of Mathematics
In this paper, the qualitative behavior of a discrete-time prey-predator model with Allee effect in prey population is discussed. Firstly, the existence of the fixed points and their topological classification are analyzed algebraically. Then, the conditions of existence for both period-doubling and Neimark--Sacker bifurcations arising from coexistence fixed point with the help of the center manifold theorem and bifurcation theory are investigated. OGY feedback control method is implemented to control chaos in the proposed model due to the emergence of bifurcations. Finally, numerical simulations are performed to support the theoretical findings.
Vanishing Ideals Of Parameterized Subgroups In A Toric Variety, Esma Baran Özkan
Vanishing Ideals Of Parameterized Subgroups In A Toric Variety, Esma Baran Özkan
Turkish Journal of Mathematics
Let $K$ be a finite field and $X$ be a complete simplicial toric variety over $K$ with split torus $T_X\cong (K^*)^n$. We give an algorithm relying on elimination theory for finding generators of the vanishing ideal of a subgroup $Y_Q$ parameterized by a matrix $Q$ which can be used to study algebraic geometric codes arising from $Y_Q$. We give a method to compute the lattice $L$ whose ideal $I_L$ is exactly $I(Y_Q)$ under a mild condition. As applications, we give precise descriptions for the lattices corresponding to some special subgroups. We also prove a Nullstellensatz type theorem valid over finite …
Inverse Nodal Problem For Sturm-Liouville Operator On A Star Graph With Nonequal Edges, Sevi̇m Durak
Inverse Nodal Problem For Sturm-Liouville Operator On A Star Graph With Nonequal Edges, Sevi̇m Durak
Turkish Journal of Mathematics
In this study, Sturm-Liouville operator was investigated on a star graph with nonequal edges. First, the behaviors of sufficiently large eigenvalues were learned, then the solution of the inverse problem was given to determine the potantial functions and parameters of the boundary condition on the star graph with the help of a dense set of nodal points and obtain a constructive solution to the inverse problems of this class.
Hermite-Hadamard-Mercer Type Inclusions For Interval-Valued Functions Via Riemann-Liouville Fractional Integrals, Hasan Kara, Muhammad Aamir Ali, Hüseyi̇n Budak
Hermite-Hadamard-Mercer Type Inclusions For Interval-Valued Functions Via Riemann-Liouville Fractional Integrals, Hasan Kara, Muhammad Aamir Ali, Hüseyi̇n Budak
Turkish Journal of Mathematics
In this research, we first establish some inclusions of fractional Hermite-Hadamard-Mercer type for interval-valued functions. Moreover, by special cases of our main results, we show that our main results reduce several inclusions obtained in the earlier works.
On A Class Of Nonlocal Porous Medium Equations Of Kirchhoff Type, Uğur Sert
On A Class Of Nonlocal Porous Medium Equations Of Kirchhoff Type, Uğur Sert
Turkish Journal of Mathematics
We study the Dirichlet problem for the degenerate parabolic equation of the Kirchhoff type \[ u_{t}-a\left(\ u\ _{L^{p}(\Omega)}^{p}\right)\sum\limits_{i=1}^{n}D_{i}\left( \left\vert u\right\vert ^{p-2}D_{i}u\right) +b\left( x,t,u\right)=f\left( x,t\right) \quad \text{in $Q_T=\Omega \times (0,T)$}, \] where $p\geq2$, $T>0$, $\Omega \subset \mathbb{R}^{n}$, $n\geq 2$, is a smooth bounded domain. The coefficient $a(\cdot)$ is real-valued function defined on $\mathbb{R}_+$ and $b(\cdot,\cdot,\tau)$ is a measurable function with variable nonlinearity in $\tau$. We prove existence of weak solutions of the considered problem under appropriate and general conditions on $a$ and $b$. Sufficient conditions for uniqueness are found and in the case $f\equiv0$ the decay rates for $\ u\ …
$(P,Q)$-Chebyshev Polynomials For The Families Of Biunivalent Function Associating A New Integral Operator With $(P,Q)$-Hurwitz Zeta Function, Sarem H. Hadi, Maslina Darus
$(P,Q)$-Chebyshev Polynomials For The Families Of Biunivalent Function Associating A New Integral Operator With $(P,Q)$-Hurwitz Zeta Function, Sarem H. Hadi, Maslina Darus
Turkish Journal of Mathematics
In the present article, making use of the $(p,q)$-Hurwitz zeta function, we provide and investigate a new integral operator. Also, we define two families ${\mathcal{S}\mathcal{M}}_{p,q}\left(\xi ,\zeta,\delta,u,\tau \right)$ and ${\mathcal{S}\mathcal{C}}_{p,q}\left(\lambda, \zeta,\vartheta,u,\tau \right)$ of biunivalent and holomorphic functions in the unit disc connected with $(p,q)$-Chebyshev Polynomials. Then we find coefficient estimates $\left a_2\right $ and $\left a_3\right .$ Finally, we obtain Fekete-Szeg$\ddot{\mathrm{o}}$ inequalities for these families.
Inverse Nodal Problems For Dirac Type Integro Differential System With A Nonlocal Boundary Condition, Baki̇ Keski̇n
Inverse Nodal Problems For Dirac Type Integro Differential System With A Nonlocal Boundary Condition, Baki̇ Keski̇n
Turkish Journal of Mathematics
In this paper, the Dirac type integro differential system\ with a nonlocal integral boundary condition is considered. First, we derive the asymptotic expressions for the solutions and large eigenvalues. Second, we provide asymptotic expressions for the nodal points and prove that a dense subset of nodal points uniquely determines the boundary condition parameter and the potential function of the considered differential system. We also provide an effective procedure for solving the inverse nodal problem.
On The Solutions Of Fractional Integro-Differential Equations Involving Ulam-Hyers-Rassias Stability Results Via $\Psi$-Fractional Derivative With Boundary Value Conditions, Kulandhivel Karthikeyan, Gobi Selvaraj Murugapandian, Özgür Ege
On The Solutions Of Fractional Integro-Differential Equations Involving Ulam-Hyers-Rassias Stability Results Via $\Psi$-Fractional Derivative With Boundary Value Conditions, Kulandhivel Karthikeyan, Gobi Selvaraj Murugapandian, Özgür Ege
Turkish Journal of Mathematics
In this paper, we study boundary value problems for the impulsive integro-differential equations via $\psi$-fractional derivative. The contraction mapping concept and Schaefer's fixed point theorem are used to produce the main results. The results reported here are more general than those found in the literature, and some special cases are presented. Furthermore, we discuss the Ulam-Hyers-Rassias stability of the solution to the proposed system.
A Fixed Point Theorem Using Condensing Operators And Its Applications To Erdelyi--Kober Bivariate Fractional Integral Equations, Anupam Das, Mohsen Rabbani, Bipan Hazarika, Sumati Kumari Panda
A Fixed Point Theorem Using Condensing Operators And Its Applications To Erdelyi--Kober Bivariate Fractional Integral Equations, Anupam Das, Mohsen Rabbani, Bipan Hazarika, Sumati Kumari Panda
Turkish Journal of Mathematics
The primary aim of this article is to discuss and prove fixed point results using the operator type condensing map, and to obtain the existence of solution of Erdelyi-Kober bivariate fractional integral equation in a Banach space. An instance is given to explain the results obtained, and we construct an iterative algorithm by sinc interpolation to find an approximate solution of the problem with acceptable accuracy.
Dissipative Mechanism And Global Attractor For Modified Swift-Hohenberg Equation In $R^{N}$, Radoslaw Czaja, Maria Kania
Dissipative Mechanism And Global Attractor For Modified Swift-Hohenberg Equation In $R^{N}$, Radoslaw Czaja, Maria Kania
Turkish Journal of Mathematics
A Cauchy problem for a modification of the Swift-Hohenberg equation in $R^{N}$ with a mildly integrable potential is considered. Applying the dissipative mechanism of fourth order parabolic equations in unbounded domains, it is shown that the equation generates a semigroup of global solutions possessing a global attractor in the scale of Bessel potential spaces and in $H^2(R^{N})$ in particular.
Initial Value Problem For Elastic System In Transversely Isotropic Inhomogeneous Media, Meltem Altunkaynak
Initial Value Problem For Elastic System In Transversely Isotropic Inhomogeneous Media, Meltem Altunkaynak
Turkish Journal of Mathematics
In this paper, we consider an initial value problem (IVP) for three dimensional elasticity system in a transversely isotropic inhomogeneous media. We will rewrite the problem in the form of Fourier images by means of Fourier transform method. After some arrangements, the problem is reduced to integral equations in the vector form. Using the properties of the vector integral equation and successive approximations method, an explicit formula for the solution of the IVP in transversely isotropic inhomogeneous media is constructed, and existence and uniqueness of the solution is stated. By a computational example, we illustrate the robustness of the method.
On Finite Nonsolvable Groups Whose Cyclic $P$-Subgroups Of Equal Order Are Conjugate, Robert Van Der Waall, Sezgi̇n Sezer
On Finite Nonsolvable Groups Whose Cyclic $P$-Subgroups Of Equal Order Are Conjugate, Robert Van Der Waall, Sezgi̇n Sezer
Turkish Journal of Mathematics
The structure of the nonsolvable (P)-groups is completely described in this article. By definition, a finite group $G$ is called a (P)-group if any two cyclic $p$-subgroups of the same order are conjugate in $G$, whenever $p$ is a prime number dividing the order of $G$.
Some Convergence, Stability, And Data Dependence Results For $K^{\Ast }$ Iterative Method Of Quasi-Strictly Contractive Mappings, Ruken Çeli̇k, Neci̇p Şi̇mşek
Some Convergence, Stability, And Data Dependence Results For $K^{\Ast }$ Iterative Method Of Quasi-Strictly Contractive Mappings, Ruken Çeli̇k, Neci̇p Şi̇mşek
Turkish Journal of Mathematics
In a recent paper, Yu et al. obtained convergence and stability results of the $K^{\ast }$ iterative method for quasi-strictly contractive mappings [An iteration process for a general class of contractive-like operators: Convergence, stability and polynomiography. AIMS Mathematics 2021; 6 (7): 6699-6714.]. To guarantee these convergence and stability results, the authors imposed some strong conditions on parametric control sequences which are used in the $K^{\ast }$ iterative method. The aim of the presented work is twofold: (a) to recapture the aforementioned results without any restrictions imposed on the mentioned parametric control sequences (b) to complete the work of Yu et …
Nonic B-Spline Algorithms For Numerical Solution Of The Kawahara Equation, Meli̇s Zorşahi̇n Görgülü
Nonic B-Spline Algorithms For Numerical Solution Of The Kawahara Equation, Meli̇s Zorşahi̇n Görgülü
Turkish Journal of Mathematics
In this paper, the nonic (9th order) B-spline functions which have not been used before for the numerical solutions of the partial differential equations by finite element methods are used to solve numerically the Kawahara equation. These approaches involve the collocation and Galerkin finite element methods based on the nonic B-spline functions in space discretization and second order scheme (Crank-Nicolson method) in time discretization. To see the accuracy of the proposed methods three test problems are demonstrated and the obtained numerical results for both of the methods are compared with the exact solution of the Kawahara equation.
Ulam's Type Stability Analysis Of Fractional Difference Equation With Impulse: Gronwall Inequality Approach, Rabia Ilyas, Mujeeb Ur Rehman
Ulam's Type Stability Analysis Of Fractional Difference Equation With Impulse: Gronwall Inequality Approach, Rabia Ilyas, Mujeeb Ur Rehman
Turkish Journal of Mathematics
In this paper, we present a new Gronwall inequality with an impulsive effect. The existence and uniqueness of the solution is investigated through fixed point theorems. Moreover, with the help of newly developed inequality Ulam's type stability criterion is developed for impulsive fractional difference equation. At last, a model is given to help the hypothetical outcome.
Existence And Uniqueness Of Mild Solutions For Mixed Caputo And Riemann-Liouville Semilinear Fractional Integrodifferential Equations With Nonlocal Conditions, Ashraf H. A. Radwan
Existence And Uniqueness Of Mild Solutions For Mixed Caputo And Riemann-Liouville Semilinear Fractional Integrodifferential Equations With Nonlocal Conditions, Ashraf H. A. Radwan
Turkish Journal of Mathematics
The purpose of this paper is to investigate the existence and uniqueness of the mild solution to a class of semilinear fractional integrodifferential equations with state-dependent nonlocal fractional conditions. Our problem includes both Caputo and Riemann-Liouville fractional derivatives. Continuous dependence of solutions on initial conditions and $\epsilon$-approximate mild solutions of the considered problem will be discussed.