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Zeros Of The Extended Selberg Class Zeta-Functions And Of Their Derivatives, Ramunas Garunkstis
Zeros Of The Extended Selberg Class Zeta-Functions And Of Their Derivatives, Ramunas Garunkstis
Turkish Journal of Mathematics
Levinson and Montgomery proved that the Riemann zeta-function ζ(s) and its derivative have approximately the same number of nonreal zeros left of the critical line. Spira showed that ζ'(1/2+it) = 0 implies that ζ(1/2+it) = 0. Here we obtain that in small areas located to the left of the critical line and near it the functions ζ(s) and ζ'(s) have the same number of zeros. We prove our result for more general zeta-functions from the extended Selberg class S. We also consider zero trajectories of a certain family of zeta-functions from S.
A Variational Study On A Natural Hamiltonian For Curves, Gözde Özkan Tükel
A Variational Study On A Natural Hamiltonian For Curves, Gözde Özkan Tükel
Turkish Journal of Mathematics
A variational study of finding critical points of the total squared torsion functional for curves in Euclidean 3-spaces is presented. Critical points of this functional also known as one of the natural Hamiltonians of curves are characterized by two Euler-Lagrange equations in terms of curvature and torsion of a curve. To solve these balance equations, the curvature of the critical curve is expressed by its torsion so that equations are completely solved by quadratures. Then two Killing fields along the critical curve are found for integrating the structural equations of the critical curve and this curve is expressed by quadratures …
Extensions And Topological Conditions Of Nj Rings, Meimei Jiang, Yao Wang, Yanli Ren
Extensions And Topological Conditions Of Nj Rings, Meimei Jiang, Yao Wang, Yanli Ren
Turkish Journal of Mathematics
A ring $R$ is said to be NJ if $J(R)=N(R)$. This paper mainly studies the relationship between NJ rings and related rings, and investigates the Dorroh extension, the Nagata extension, the Jordan extension, and some other extensions of NJ rings. At the same time, we also prove that if $R$ is a weakly 2-primal $\alpha$-compatible ring with an isomorphism $\alpha$ of $R$, then $R[x;\alpha]$ is NJ; if $R$ is a weakly 2-primal $\delta$-compatible ring with a derivation $\delta$ of $R$, then $R[x;\delta]$ is NJ. Moreover, we consider some topological conditions for NJ rings and show for a NJ ring $R$ …
Degenerate Maximal Hyponormal Differential Operators For The First Order, Meltem Sertbaş, Fati̇h Yilmaz
Degenerate Maximal Hyponormal Differential Operators For The First Order, Meltem Sertbaş, Fati̇h Yilmaz
Turkish Journal of Mathematics
In this study, all maximal hyponormal extensions are given for the degenerate first order in the Hilbert space of vector-functions on a finite interval. The extensions are defined in terms of the boundary values. The structure of the spectrum of the maximal hyponormal extensions is also investigated.
The $X$-Coordinates Of Pell Equations And Padovan Numbers, Salah Eddine Rihane, Mohand Ouamar Hernane, Alain Togbe
The $X$-Coordinates Of Pell Equations And Padovan Numbers, Salah Eddine Rihane, Mohand Ouamar Hernane, Alain Togbe
Turkish Journal of Mathematics
In this paper, we show that there is at most one value of the positive integer $X$ participating in the Pell equation $X^2-dY^2=k$, where $k\in\{\pm1,\pm4\}$, which is a Padovan number, with a few exceptions that we completely characterize.
A Neutral Relation Between Metallic Structure And Almost Quadratic $\Phi $-Structure, Si̇nem Gönül, İrem Küpeli̇ Erken, Azi̇z Yazla, Cengi̇zhan Murathan
A Neutral Relation Between Metallic Structure And Almost Quadratic $\Phi $-Structure, Si̇nem Gönül, İrem Küpeli̇ Erken, Azi̇z Yazla, Cengi̇zhan Murathan
Turkish Journal of Mathematics
In this paper, we give a neutral relation between metallic structure and almost quadratic metric $\phi $-structure. Considering $N$ as a metallic Riemannian manifold, we show that the warped product manifold $\mathbb{R} \times _{f}N$ has an almost quadratic metric $\phi $-structure. We define Kenmotsu quadratic metric manifolds, which include cosymplectic quadratic manifolds when $\beta =0$. Then we give nice almost quadratic metric $\phi $-structure examples. In the last section, we construct a quadratic $\phi $-structure on the hypersurface $M^{n}$ of a locally metallic Riemannian manifold $\tilde{M}^{n+1}.$
Enveloping Algebras Of Color Hom-Lie Algebras, Abdoreza Armakan, Sergei Silvestrov, Mohammad Reza Farhangdoost
Enveloping Algebras Of Color Hom-Lie Algebras, Abdoreza Armakan, Sergei Silvestrov, Mohammad Reza Farhangdoost
Turkish Journal of Mathematics
In this paper, the universal enveloping algebra of color hom-Lie algebras is studied. A construction of the free involutive hom-associative color algebra on a hom-module is described and applied to obtain the universal enveloping algebra of an involutive hom-Lie color algebra. Finally, the construction is applied to obtain the well-known Poincaré-Birkhoff-Witt theorem for Lie algebras to the enveloping algebra of an involutive color hom-Lie algebra.
Properties In $L_P$ Of Root Functions For A Nonlocal Problem With Involution, Leonid Kritskov, Makhmud Sadybekov, Abdizhahan Sarsenbi
Properties In $L_P$ Of Root Functions For A Nonlocal Problem With Involution, Leonid Kritskov, Makhmud Sadybekov, Abdizhahan Sarsenbi
Turkish Journal of Mathematics
The spectral problem $-u''(x)+\alpha u''(-x)=\lambda u(x)$, $-1$%lt; $x$ < $1$, with nonlocal boundary conditions $u(-1)=\beta u(1)$, $u'(-1)=u'(1)$, is studied in the spaces $L_p(-1,1)$ for any $\alpha\in (-1,1)$ and $\beta\ne\pm 1$. It is proved that if $r=\sqrt{(1-\alpha)/(1+\alpha)}$ is irrational then the system of its eigenfunctions is complete and minimal in $L_p(-1,1)$ for any $p>1$, but does not form a basis. In the case of a rational value of $r$, the way of supplying this system with associated functions is specified to make all the root functions a basis in $L_p(-1,1)$.
On Linear Dynamics Of Sets Of Operators, Mohamed Amouch, Otmane Benchiheb
On Linear Dynamics Of Sets Of Operators, Mohamed Amouch, Otmane Benchiheb
Turkish Journal of Mathematics
Let $X$ be a complex topological vector space with $dim(X)>1$ and $\mathcal{B}(X)$ the set of all continuous linear operators on $X$. The concept of hypercyclicity for a subset of $\mathcal{B}(X)$ was introduced in [1]. In this work, we introduce the notion of hypercyclic criterion for a subset of $\mathcal{B}(X)$. We extend some results known for a single operator and $C_0$-semigroup to a subset of $\mathcal{B}(X)$ and we give applications for $C$-regularized groups of operators.
On Product Complex Finsler Manifolds, Hongchuan Xia, Qian Wei
On Product Complex Finsler Manifolds, Hongchuan Xia, Qian Wei
Turkish Journal of Mathematics
Let $(M, F)$ be the product complex Finsler manifold of two strongly pseudoconvex complex Finsler manifolds $(M_1, F_1)$ and $(M_2, F_2)$ with $F=\sqrt{f(K, H)}$ and $K=F_1^2$, $H=F_2^2$. In this paper, we prove that $(M, F)$ is a weakly Käahler-Finsler (resp. weakly complex Berwald) manifold if and only if $(M_1, F_1)$ and $(M_2, F_2)$ are both weakly Kähler-Finsler (resp. weakly complex Berwald) manifolds, which is independent of the choice of function $f$. Meanwhile, we prove that $(M, F)$ is a complex Landsberg manifold if and only if either $(M_1, F_1)$ and $(M_2, F_2)$ are both complex Landsberg manifolds and $f=c_1K+c_2H$ with …
Properties Of A Generalized Class Of Analytic Functions With Coefficient Inequality, Ben Wongsaijai, Nattakorn Sukantamala
Properties Of A Generalized Class Of Analytic Functions With Coefficient Inequality, Ben Wongsaijai, Nattakorn Sukantamala
Turkish Journal of Mathematics
Let $(\beta_n)_{n\ge 2}$ be a sequence of nonnegative real numbers and $\delta$ be a positive real number. We introduce the subclass $\mathcal{A}(\beta_n,\delta)$ of analytic functions, with the property that the Taylor coefficients of the function $f$ satisfies $\sum_{n\ge2}^{\infty}\beta_n a_n \le \delta$, where $f(z)=z+\sum_{n=2}^{\infty}a_nz^n$. The class $\mathcal{A}(\beta_n,\delta)$ contains nonunivalent functions for some choices of $(\beta_n)_{n\ge 2}$. In this paper, we provide some general properties of functions belonging to the class $\mathcal{A}(\beta_n,\delta)$, such as the radii of univalence, distortion theorem, and invariant property. Furthermore, we derive the best approximation of an analytic function in such class by using the semiinfinite quadratic programming. …
Some General Results On Fractional Banach Sets, Faruk Özger
Some General Results On Fractional Banach Sets, Faruk Özger
Turkish Journal of Mathematics
The gamma function which is expressed by an improper integral is used to establish the fractional difference operators and fractional Banach sets. In this study, we achieve some comprehensive and complementary results related to characterizations of the matrix classes of fractional Banach sets. We also obtain some identities or inequalities for the Hausdorff measure of noncompactness of the corresponding matrix operators, and finally find the necessary and sufficient conditions for those matrix operators to be compact.
A Bernstein-Type Theorem For $\Xi$-Submanifolds Withflat Normal Bundle In The Euclidean Spaces, Xu-Yong Jiang, He-Jun Sun, Peibiao Zhao
A Bernstein-Type Theorem For $\Xi$-Submanifolds Withflat Normal Bundle In The Euclidean Spaces, Xu-Yong Jiang, He-Jun Sun, Peibiao Zhao
Turkish Journal of Mathematics
$\xi$-Submanifolds in the Euclidean spaces are a natural extension of self-shrinkers and a generalization of $\lambda$-hypersurfaces. Moreover, $\xi$-submanifolds are expected to take the place of submanifolds with parallel mean curvature vector. In this paper, we establish a Bernstein-type theorem for $\xi$-submanifolds in the Euclidean spaces. More precisely, we prove that an $n$-dimensional smooth graphic $\xi$-submanifold with flat normal bundle in $\mathbb{R}^{n+p}$ is an affine $n$-plane.
Converse Theorems In Lyapunov's Second Method And Applications For Fractional Order Systems, Javier Gallegos, Manuel Duarte-Mermoud
Converse Theorems In Lyapunov's Second Method And Applications For Fractional Order Systems, Javier Gallegos, Manuel Duarte-Mermoud
Turkish Journal of Mathematics
We establish a characterization of the Lyapunov and Mittag-Leffler stability through (fractional) Lyapunov functions, by proving converse theorems for Caputo fractional order systems. A hierarchy for the Mittag-Leffler order convergence is also proved which shows, in particular, that fractional differential equation with derivation order lesser than one cannot be exponentially stable. The converse results are then applied to show that if an integer order system is (exponentially) stable, then its corresponding fractional system, obtained from changing its differentiation order, is (Mittag-Leffler) stable. Hence, available integer order control techniques can be disposed to control nonlinear fractional systems. Finally, we provide examples …
On The Cover Ideals Of Chordal Graphs, Nursel Erey
On The Cover Ideals Of Chordal Graphs, Nursel Erey
Turkish Journal of Mathematics
The independence complex of a chordal graph is known to be shellable which is equivalent to the fact that cover ideal of a chordal graph has linear quotients. We use this result to obtain recursive formulas for the Betti numbers of cover ideals of chordal graphs. Moreover, we give a new proof of such result which yields different shellings of the independence complex.
A Circulant Functional Equation For The Additive Function And Its Stability, Vichian Laohakosol, Watcharapon Pimsert, Kanet Ponpetch
A Circulant Functional Equation For The Additive Function And Its Stability, Vichian Laohakosol, Watcharapon Pimsert, Kanet Ponpetch
Turkish Journal of Mathematics
A general solution of a matrix functional equation involving circulant matrices of the additive function is determined, and its stability is established.
On The Chebyshev Coefficients For A General Subclass Of Univalentfunctions, Şahsene Altinkaya, Si̇bel Yalçin Tokgöz
On The Chebyshev Coefficients For A General Subclass Of Univalentfunctions, Şahsene Altinkaya, Si̇bel Yalçin Tokgöz
Turkish Journal of Mathematics
In this work, considering a general subclass of univalent functions and using the Chebyshev polynomials, we obtain coefficient expansions for functions in this class.
Linear Methods Of Summing Fourier Series And Approximation In Weighted Orliczspaces, Sadulla Jafarov
Linear Methods Of Summing Fourier Series And Approximation In Weighted Orliczspaces, Sadulla Jafarov
Turkish Journal of Mathematics
In the present work, we investigate estimates of the deviations of the periodic functions from the linear operators constructed on the basis of its Fourier series in reflexive weighted Orlicz spaces with Muckenhoupt weights. In particular, the orders of approximation of Zygmund and Abel-Poisson means of Fourier trigonometric series were estimated by the $k-th$~modulus of smoothness in reflexive weighted Orlicz spaces with Muckenhoupt weights.
The Diameter Vulnerability Of The Generalized Petersen Graph ${Gp[Tk,K]}$, Gülnaz Boruzanli Eki̇nci̇, John Baptist Gauci
The Diameter Vulnerability Of The Generalized Petersen Graph ${Gp[Tk,K]}$, Gülnaz Boruzanli Eki̇nci̇, John Baptist Gauci
Turkish Journal of Mathematics
The diameter of a graph gives the length of the longest path among all the shortest paths between any two vertices of the graph, and the diameter vulnerability problem measures the change in the diameter upon the deletion of edges. In this paper we determine the diameter vulnerability of the generalized Petersen graph $GP[tk,k]$, for integers $t\geq 2$ and $k\geq 1$, and show that (except for some small cases) the diameter remains unchanged upon the deletion of one edge. This work contributes towards a solution of the well-known $(\Delta, D, D', s)$-problem, which attempts to find large graphs with maximum …
Construction Of The Second Hankel Determinant For A New Subclass Ofbi-Univalent Functions, Şahsene Altinkaya, Si̇bel Yalçin Tokgöz
Construction Of The Second Hankel Determinant For A New Subclass Ofbi-Univalent Functions, Şahsene Altinkaya, Si̇bel Yalçin Tokgöz
Turkish Journal of Mathematics
In this paper, we will discuss a newly constructed subclass of bi-starlike functions. Furthermore, we establish bounds for the coefficients and get the second Hankel determinant for the class $S_{\Sigma }(\alpha ,\beta ).$
Description Of Invariant Subspaces In Terms Of Berezin Symbols, Suna Saltan
Description Of Invariant Subspaces In Terms Of Berezin Symbols, Suna Saltan
Turkish Journal of Mathematics
We consider the stretching operator $\left( T_{w}f\right) \left( z\right) =f(wz)$ and the multiple shift operator $S^{n}f=z^{n}f$ on the Hardy spaces $% H^{p}(\mathbb{D})$ $\left( 1\leq p
Free Modules And Crossed Modules Of $R$-Algebroids, Osman Avcioğlu, İbrahi̇m İlker Akça
Free Modules And Crossed Modules Of $R$-Algebroids, Osman Avcioğlu, İbrahi̇m İlker Akça
Turkish Journal of Mathematics
In this paper, first, we construct the free modules and precrossed modules of $R$-algebroids. Then we introduce the Peiffer ideal of a precrossed module and use it to construct the free crossed module.
Generalization Of The Cayley Transform In 3d Homogeneous Geometries, Zlatko Erjavec
Generalization Of The Cayley Transform In 3d Homogeneous Geometries, Zlatko Erjavec
Turkish Journal of Mathematics
The Cayley transform maps the unit disk onto the upper half-plane, conformally and isometrically. In this paper, we generalize the Cayley transform in three-dimensional homogeneous geometries which are fiber bundles over the hyperbolic plane. Obtained generalizations are isometries between existing models in corresponding homogeneous geometries. Particularly, constructed isometry between two models of { $\widetilde{SL(2,\mathbb{R})}$} geometry is nontrivial and enables comparison and transfer of known and even future results between these two models.
Trigonometric Expressions For Infinite Series Involving Binomial Coefficients, Nadia Li
Trigonometric Expressions For Infinite Series Involving Binomial Coefficients, Nadia Li
Turkish Journal of Mathematics
By means of the hypergeometric series approach, we present a new proof of Sun's conjecture on trigonometric series, which is simpler than the original one due to Sun and Meng. Several further infinite series identities are shown as examples.
On The Asymptotic Behavior Of Solution Of Certain Systems Of Volterra Equations, Ewa Schmeidel, Malgorzata Zdanowicz
On The Asymptotic Behavior Of Solution Of Certain Systems Of Volterra Equations, Ewa Schmeidel, Malgorzata Zdanowicz
Turkish Journal of Mathematics
This paper is concerned with the asymptotic property of the solution of a system of the linear Volterra difference equations. The criterion for the existence of a solution of the considered system that is asymptotically equivalent to a given sequence is established. %The results generalize some recent results. The results presented here improve and generalize the results published by Diblik et al. Unlike in those works, here periodicity of the nonhomogeneous term of the equation is not assumed. Examples illustrate the obtained results.
Almost Paracontact Structures Obtained From $G_{2(2)}^*$ Structures, Nüli̇fer Özdemi̇r, Şi̇ri̇n Aktay, Mehmet Solgun
Almost Paracontact Structures Obtained From $G_{2(2)}^*$ Structures, Nüli̇fer Özdemi̇r, Şi̇ri̇n Aktay, Mehmet Solgun
Turkish Journal of Mathematics
In this paper, we construct almost paracontact metric structures by using the fundamental 3-forms of manifolds with $G_{2(2)}^*$ structures. The existence of certain almost paracontact metric structures is investigated due to the properties of the 2-fold vector cross-product. Furthermore, we give some relations between the classes of $G_{2(2)}^*$ structures and almost paracontact metric structures.