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A Note On Dynamics In Functional Spaces, Liangxue Peng, Chong Yang Jan 2017

A Note On Dynamics In Functional Spaces, Liangxue Peng, Chong Yang

Turkish Journal of Mathematics

In this note, we study topologically transitive and hypercyclic composition operators on $C_p(X)$ or $C_k(X)$. We prove that if $G$ is a semigroup of continuous self maps of a countable metric space $X$ with the following properties: (1) every element of $G$ is one-to-one on $X$, (2) the action of $G$ is strongly run-away on $X$, then the action of $\hat{G}$ on $C_p(X)$ is topologically transitive and hypercyclic. If $G$ is the set of all one-to-one and continuous self maps of $\mathbb{R}\setminus \mathbb{Z}$, then the action of $\hat{G}$ on $C_k(\mathbb{R}\setminus \mathbb{Z})$ is hypercyclic. We also show that the action of …


Free Storage Basis Conversion Over Finite Fields, Ersan Akyildiz, Ndangang Yampa Harold, Ahmet Sinak Jan 2017

Free Storage Basis Conversion Over Finite Fields, Ersan Akyildiz, Ndangang Yampa Harold, Ahmet Sinak

Turkish Journal of Mathematics

Representation of a field element plays a crucial role in the efficiency of field arithmetic. If an efficient representation of a field element in one basis exists, then field arithmetic in the hardware and/or software implementations becomes easy. Otherwise, a basis conversion to an efficient one is searched for easier arithmetic. However, this conversion often brings a storage problem for transition matrices associated with these bases. In this paper, we study this problem for conversion between normal and polynomial bases in the extension field $\mathbb{F}_{q^p}$ over $\mathbb{F}_q$ where $q=p^n$. We construct transition matrices that are of a special form. This …


Quasi-Metric Trees And $Q$-Hyperconvex Hulls, Zechariah Mushaandja, Olivier Olela Otafudu Jan 2017

Quasi-Metric Trees And $Q$-Hyperconvex Hulls, Zechariah Mushaandja, Olivier Olela Otafudu

Turkish Journal of Mathematics

The investigation of metric trees began with J. Tits in 1977. Recently we studied a more general notion of quasi-metric tree. In the current article we prove, among other facts, that the $q$-hyperconvex hull of a $q$-hyperconvex $T_0$-quasi-metric tree is itself a $T_0$-quasi-metric tree. This is achieved without using the four-point property, a geometric concept used by Aksoy and Maurizi to show that every complete metric tree is hyperconvex.


Lie Symmetry Analysis And Exact Solutions Of The Sawada-Kotera Equation, Youwei Zhang Jan 2017

Lie Symmetry Analysis And Exact Solutions Of The Sawada-Kotera Equation, Youwei Zhang

Turkish Journal of Mathematics

In the present paper, the Sawada-Kotera equation is considered by Lie symmetry analysis. All of the geometric vector fields to the Sawada-Kotera equation are obtained, and then the symmetry reductions and exact solutions of the Sawada-Kotera equation are investigated. Our results show that symmetry analysis is a very efficient and powerful technique in finding the solution of the proposed equation.


Dirac Systems With Regular And Singular Transmission Effects, Eki̇n Uğurlu Jan 2017

Dirac Systems With Regular And Singular Transmission Effects, Eki̇n Uğurlu

Turkish Journal of Mathematics

In this paper, we investigate the spectral properties of singular eigenparameter dependent dissipative problems in Weyl's limit-circle case with finite transmission conditions. In particular, these transmission conditions are assumed to be regular and singular. To analyze these problems we construct suitable Hilbert spaces with special inner products and linear operators associated with these problems. Using the equivalence of the Lax-Phillips scattering function and Sz-Nagy-Foiaş characteristic functions we prove that all root vectors of these dissipative operators are complete in Hilbert spaces.


A Mehrotra Predictor-Corrector Interior-Point Algorithm For Semidefinite Optimization, Mohammad Pirhaji, Maryam Zangiabadi, Hossein Mansouri Jan 2017

A Mehrotra Predictor-Corrector Interior-Point Algorithm For Semidefinite Optimization, Mohammad Pirhaji, Maryam Zangiabadi, Hossein Mansouri

Turkish Journal of Mathematics

This paper proposes a second-order Mehrotra-type predictor-corrector feasible interior-point algorithm for semidefinite optimization problems. In each iteration, the algorithm computes the Newton search directions through a new form of combination of the predictor and corrector directions. Using the Ai-Zhang wide neighborhood for linear complementarity problems, it is shown that the complexity bound of the algorithm is $O(\sqrt{n}\log \varepsilon^{-1})$ for the Nesterov-Todd search direction and $O({n}\log \varepsilon^{-1})$ for the Helmberg-Kojima-Monteiro search directions.


On The Attached Prime Ideals Of Localcohomology Modules Defined By A Pair Of Ideals, Zohreh Habibi, Maryam Jahangiri, Khadijeh Ahmadi Amoli Jan 2017

On The Attached Prime Ideals Of Localcohomology Modules Defined By A Pair Of Ideals, Zohreh Habibi, Maryam Jahangiri, Khadijeh Ahmadi Amoli

Turkish Journal of Mathematics

Let $I$ and $J$ be two ideals of a commutative Noetherian ring $R$ and $M$ be an $R$-module of dimension $d$. For each $i\in N_0$ let $H^{i}_{I,J}(-)$ denote the $i$-th right derived functor of $\Gamma_{I,J}(-)$, where $\Gamma _{I,J}(M):=\{x \in M : I^{n}x\subseteq Jx \ \text {for} \ n\gg 1\}$. If $R$ is a complete local ring and $M$ is finite, then attached prime ideals of $H^{d-1}_{I,J}(M)$ are computed by means of the concept of co-localization. Moreover, we illustrate the attached prime ideals of $H^{t}_{I,J}(M)$ on a nonlocal ring $R$, for $t= \dim M$ and $t= (I,J,M)$, where $(I,J,M)$ is the …


On Orthogonal Systems Of Shifts Of Scaling Function On Local Fields Of Positive Characteristic, Gleb Sergeevich Berdnikov, Iuliia Sergeevna Kruss, Sergey Fedorovich Lukomskii Jan 2017

On Orthogonal Systems Of Shifts Of Scaling Function On Local Fields Of Positive Characteristic, Gleb Sergeevich Berdnikov, Iuliia Sergeevna Kruss, Sergey Fedorovich Lukomskii

Turkish Journal of Mathematics

We present a new method for constructing an orthogonal step scaling function on local fields of positive characteristic, which generates multiresolution analysis.


Existence Of Unpredictable Solutions And Chaos, Marat Akhmet, Mehmet Onur Fen Jan 2017

Existence Of Unpredictable Solutions And Chaos, Marat Akhmet, Mehmet Onur Fen

Turkish Journal of Mathematics

Recently we introduced the concept of Poincaré chaos. In the present paper, by means of the Bebutov dynamical system, an unpredictable solution is considered as a generator of the chaos in a quasilinear system. The results can be easily extended to different types of differential equations. An example of an unpredictable function is provided. A proper irregular behavior in coupled Duffing equations is observed through simulations.


Exponent Of Local Ring Extensions Of Galois Rings And Digraphs Of The $K$Th Power Mapping, Ittiwat Tocharoenirattisai, Yotsanan Meemark Jan 2017

Exponent Of Local Ring Extensions Of Galois Rings And Digraphs Of The $K$Th Power Mapping, Ittiwat Tocharoenirattisai, Yotsanan Meemark

Turkish Journal of Mathematics

In this paper, we consider a local extension $R$ of the Galois ring of the form $GR(p^{n},d)[x]/(f(x)^{a})$, where $n,d$, and $a$ are positive integers; $p$ is a prime; and $f(x)$ is a monic polynomial in $GR(p^{n},d)[x]$ of degree $r$ such that the reduction $\overline{f}(x)$ in $\mathbb{F}_{p^{d}}[x]$ is irreducible. We establish the exponent of $R$ without complete determination of its unit group structure. We obtain better analysis of the iteration graphs $G^{(k)}(R)$ induced from the $k$th power mapping including the conditions on symmetric digraphs. In addition, we work on the digraph over a finite chain ring $R$. The structure of $G^{(k)}_{2}(R)$ …


Topological Entropies Of A Class Of Constrained Systems, Yanni Ma, Bingzhe Hou Jan 2017

Topological Entropies Of A Class Of Constrained Systems, Yanni Ma, Bingzhe Hou

Turkish Journal of Mathematics

In this paper, we consider a class of constrained systems named double upper bounds $(p,q)$-constrained systems ($(p,q)$-DUB systems in brief), which are one-dimensional subshifts of finite type. We determinate the topological entropies (Shannon capacities) $C(p,q)$ of all $(p,q)$-DUB systems and consequently order all $(p,q)$-DUB systems according to the size of topological entropies. In particular, $C(p, \infty)=C(p+1, p+1)$ are the only equalities possible among the topological entropies of $(p,q)$-DUB systems.


Koebe Sets For The Class Of Functions Convex In Two Directions, Leopold Koczan, Pawel Zaprawa Jan 2017

Koebe Sets For The Class Of Functions Convex In Two Directions, Leopold Koczan, Pawel Zaprawa

Turkish Journal of Mathematics

In this paper, we consider a class $K_\alpha$ of all functions $f$ univalent in the unit disk $\Delta$ that are normalized by $f(0)=f'(0)-1=0$ while the sets $f(\Delta)$ are convex in two symmetric directions: $e^{i\alpha\pi/2}$ and $e^{-i\alpha\pi/2}$, $\alpha\in[0,1]$. It means that the intersection of $f(\Delta)$ with each straight line having the direction $e^{i\alpha\pi/2}$ or $e^{-i\alpha\pi/2}$ is either a compact set or an empty set. We find the Koebe set for $K_\alpha$. Moreover, we perform the same operation for functions in $K_{\beta, \gamma}$, i.e. for functions that are convex in two fixed directions: $e^{i\beta\pi/2}$ and $e^{i\gamma\pi/2}$, $-1\leq \beta\leq\gamma \leq 1$.


Warped Product Spaces With Ricci Conditions, Sang Deok Lee, Byung Hak Kim, Jin Hyuk Choi Jan 2017

Warped Product Spaces With Ricci Conditions, Sang Deok Lee, Byung Hak Kim, Jin Hyuk Choi

Turkish Journal of Mathematics

In this paper, we study the Ricci soliton in the Riemannian products$M=R^n \times B$ and warped products $M=R \times _f B$ of theEuclidean space and Riemannian manifolds, and the gradient Riccisoliton in the warped products $M=S^1 \times _f B$ of 1-dimensionalcircle and Riemannian manifolds. Moreover, we introduce the concept ofthe generalized Ricci soliton and we suggest the method of constructionof the Riemannian manifold $(M, g)$ with a Ricci soliton $g$.Finally, we also study the Lorentzian warped products with the Riccisoliton.


Minimizing Graph Of The Connected Graphs Whose Complements Are Bicyclic With Two Cycles, Muhammad Javaid Jan 2017

Minimizing Graph Of The Connected Graphs Whose Complements Are Bicyclic With Two Cycles, Muhammad Javaid

Turkish Journal of Mathematics

In a certain class of graphs, a graph is called minimizing if the least eigenvalueof its adjacency matrix attains the minimum. A connected graph containing two or three cycles is called a bicyclic graph if its number of edges is equal to its number of vertices plus one. In this paper, we characterize the minimizinggraph among all the connected graphs that belong to a class of graphs whose complements are bicyclic with two cycles.


A Note On The Conjugacy Problem For Finite Sylow Subgroups Of Linear Pseudofinite Groups, Pinar Uğurlu Kowalski̇ Jan 2017

A Note On The Conjugacy Problem For Finite Sylow Subgroups Of Linear Pseudofinite Groups, Pinar Uğurlu Kowalski̇

Turkish Journal of Mathematics

We prove the conjugacy of Sylow $2$-subgroups in pseudofinite $\mathfrak{M}_c$ (in particular linear) groups under the assumption that there is at least one finite Sylow $2$-subgroup. We observe the importance of the pseudofiniteness assumption by analyzing an example of a linear group with nonconjugate finite Sylow $2$-subgroups, which was constructed by Platonov.


On The Extended Spectrum Of Some Quasinormal Operators, Meltem Sertbaş, Fati̇h Yilmaz Jan 2017

On The Extended Spectrum Of Some Quasinormal Operators, Meltem Sertbaş, Fati̇h Yilmaz

Turkish Journal of Mathematics

In this paper we consider some extended eigenvalue problems for some quasinormal operators. The spectrum of an algebra homomorphism defined by a compact normal operator is also investigated.


More Accurate Jensen-Type Inequalities For Signed Measures Characterized Via Green Function And Applications, Mario Krnic, Josip Pecaric, Mirna Rodic Jan 2017

More Accurate Jensen-Type Inequalities For Signed Measures Characterized Via Green Function And Applications, Mario Krnic, Josip Pecaric, Mirna Rodic

Turkish Journal of Mathematics

In this paper we derive several improved forms of the Jensen inequality, giving the necessary and sufficient conditions for them to hold in the case of the real Stieltjes measure not necessarily positive.The obtained relations are characterized via the Green function. As an application, our main results are employed for constructing some classes of exponentially convex functions and some Cauchy-type means.


Some Notes On $Gqn$ Rings, Long Wang, Junchao Wei Jan 2017

Some Notes On $Gqn$ Rings, Long Wang, Junchao Wei

Turkish Journal of Mathematics

A ring $R$ is called ageneralized quasinormal ring (abbreviated as $GQN$ ring) if $ea∈N(R)$ for each $e∈ E(R)$ and $a∈ N(R)$. The class of $GQN$ rings is a proper generalization of quasinormal rings and $NI$ rings. Many properties of quasinormal rings are extended to $GQN$ rings. For a$GQN$ ring $R$ and $a∈ R$, it is shown that:1) if $a$ is a regular element, then $a$ is a strongly regular element;2) if $a$ is an exchange element, then $a$ is clean;3) if $R$ is a semiperiodic ring with $J(R)\neq N(R)$, then $R$ is commutative;4) if $R$ is an $MVNR$, then $R$ …


A Novel Kind Of Akns Integrable Couplings And Their Hamiltonian Structures, Yu-Juan Zhang, Wen-Xiu Ma, Ömer Ünsal Jan 2017

A Novel Kind Of Akns Integrable Couplings And Their Hamiltonian Structures, Yu-Juan Zhang, Wen-Xiu Ma, Ömer Ünsal

Turkish Journal of Mathematics

We present a novel hierarchy of AKNS integrable couplings based on a specific semidirect sum of Lie algebras associated with sl$(2)$. By applying the variational identity, we derive a bi-Hamiltonian structure of the resulting coupling systems, thereby showing their Liouville integrability.


Modules Satisfying Double Chain Condition On Nonfinitely Generated Submodules Have Krull Dimension, Maryam Davoudian Jan 2017

Modules Satisfying Double Chain Condition On Nonfinitely Generated Submodules Have Krull Dimension, Maryam Davoudian

Turkish Journal of Mathematics

We prove the result in the title. We study submodules $N$ of a module $M$ such that whenever $\frac{M}{N}$ satisfies the double infinite chain condition so does $M$.Moreover, we observe that an $\alpha $-atomic module, where $\alpha\geq 2$ is an ordinal number, satisfies the previous chain if and only if it satisfies the descending chain condition on nonfinitely generated submodules.


Arf Numerical Semigroups, Sedat İlhan, Hali̇l İbrahi̇m Karakaş Jan 2017

Arf Numerical Semigroups, Sedat İlhan, Hali̇l İbrahi̇m Karakaş

Turkish Journal of Mathematics

The aim of this work is to exhibit the relationship between the Arf closure of a numerical semigroup$S$ and its Lipman semigroup $L(S).$ This relationship is then used to give direct proofs of some characterizations of Arf numerical semigroups through their Lipman sequences of semigroups. We also give an algorithmic construction of the Arf closure of a numerical semigroup via its Lipman sequence of semigroups.


On Hölder Continuity Of Approximate Solution Maps To Vector Equilibrium Problems, Lam Quoc Anh, Kien Trung Nguyen, Tran Ngoc Tam Jan 2017

On Hölder Continuity Of Approximate Solution Maps To Vector Equilibrium Problems, Lam Quoc Anh, Kien Trung Nguyen, Tran Ngoc Tam

Turkish Journal of Mathematics

In this article, we considerparametric vector equilibrium problems in normed spaces. Sufficientconditions for Hölder continuity of approximate solution mappingswhere they are set-valued are established. As applications of theseresults, the Hölder continuity of the approximate solutionmappings for vector optimization problems and vector variationalinequalities are derived at the end of the paper. Our results arenew and include the existing ones in the literature.


Universal Central Extensions Of $\Mathfrak{Sl}(M, N, A)$ Over Associative Superalgebras, Xabier García-Martínez, Manuel Ladra Jan 2017

Universal Central Extensions Of $\Mathfrak{Sl}(M, N, A)$ Over Associative Superalgebras, Xabier García-Martínez, Manuel Ladra

Turkish Journal of Mathematics

We find the universal central extension of the matrix superalgebras $\mathfrak{sl}(m, n, A)$, where $A$ is an associative superalgebra and $m+n = 3, 4$, and its relation with the Steinberg superalgebra $\mathfrak{st}(m, n,A)).$ We calculate $H_2$ $(\mathfrak{sl}(m, n,A))$ and $H_2$ $(\mathfrak{st}(m, n,A))$. Finally, we introduce a new method using the nonabelian tensor product of Lie superalgebras to and the connection between $H_2$ $(\mathfrak{sl}(m, n, A))$ and the cyclic homology of associative superalgebras for $m+n \geq 3$.


Generalization Of The Gauss--Lucas Theorem For Bicomplex Polynomials, Mahmood Bidkham, Sara Ahamadi Jan 2017

Generalization Of The Gauss--Lucas Theorem For Bicomplex Polynomials, Mahmood Bidkham, Sara Ahamadi

Turkish Journal of Mathematics

The aim of this paper is to extend the domain of the Gauss—Lucas theorem from the set of complex numbers to the set of bicomplex numbers. We also discuss a bicomplex version of another compact generalization of the Gauss—Lucas theorem.


Piecewise Asymptotically Almost Periodic Solution Of Neutral Volterra Integro-Differential Equations With Impulsive Effects, Zhinan Xia Jan 2017

Piecewise Asymptotically Almost Periodic Solution Of Neutral Volterra Integro-Differential Equations With Impulsive Effects, Zhinan Xia

Turkish Journal of Mathematics

In this paper, we investigate the existence and uniqueness ofa piecewise asymptotically almost periodic mild solution tononautonomous neutral Volterra integro-differential equations withimpulsive effects in Banach space. The working tools are based onthe Krasnoselskii's fixed point theorem and semigroup theory. Inorder to illustrate our main results, we study the piecewiseasymptotically almost periodic solution of the impulsive partialdifferential equations with Dirichlet conditions.


Evaluation Of Euler-Like Sums Via Hurwitz Zeta Values, Ayhan Di̇l, Istvan Mezo, Mehmet Cenkci̇ Jan 2017

Evaluation Of Euler-Like Sums Via Hurwitz Zeta Values, Ayhan Di̇l, Istvan Mezo, Mehmet Cenkci̇

Turkish Journal of Mathematics

In this paper we collect two generalizations of harmonic numbers (namelygeneralized harmonic numbers and hyperharmonic numbers) under one roof.Recursion relations, closed-form evaluations, and generating functions of thisunified extension are obtained. In light of this notion we evaluate someparticular values of Euler sums in terms of odd zeta values. We alsoconsider the noninteger property and some arithmetical aspects of this unifiedextension.


On The Bounds Of The Forgotten Topological Index, Suresh Elumalai, Toufik Mansour, Mohammad Ali Rostami Jan 2017

On The Bounds Of The Forgotten Topological Index, Suresh Elumalai, Toufik Mansour, Mohammad Ali Rostami

Turkish Journal of Mathematics

The forgotten topological index is defined as the sum of cubes of the degrees of the vertices of the molecular graph $G.$ In this paper, we obtain, analyze, and compare various lower bounds for the forgotten topological index involving the number of vertices, edges, and maximum and minimum vertex degree. Then we give Nordhaus--Gaddum-type inequalities for the forgotten topological index and coindex. Finally, we correct the number of extremal chemical trees on 15 vertices.


On Armendariz-Like Properties In Amalgamated Algebras Along Ideals, Abdeslam Mimouni, Najib Mahdou, Mounir El Ourrachi Jan 2017

On Armendariz-Like Properties In Amalgamated Algebras Along Ideals, Abdeslam Mimouni, Najib Mahdou, Mounir El Ourrachi

Turkish Journal of Mathematics

Let $f: A\rightarrow B$ be a ring homomorphism and $J$ be an ideal of $B$. In this paper, we investigate the transfer of Armendariz-like properties to the amalgamation of $A$ with $B$ along $J$ with respect to $f$ (denoted by $A\bowtie^fJ)$ introduced and studied by D'Anna, Finocchiaro, and Fontana in 2009. Our aim is to provide necessary and sufficient conditions for $A\bowtie^fJ$ to be an Armendariz ring, nil-Armendariz ring, and weak Armendariz ring.


On Generalized Kropina Change Of $M$Th Root Finsler Metrics With Special Curvature Properties, Bankteshwar Tiwari, Ghanashyam Kr. Prajapati Jan 2017

On Generalized Kropina Change Of $M$Th Root Finsler Metrics With Special Curvature Properties, Bankteshwar Tiwari, Ghanashyam Kr. Prajapati

Turkish Journal of Mathematics

In the present paper, we consider generalized Kropina change of $m$th root Finsler metrics and prove that every generalized Kropina change of $m$th root Finsler metrics with isotropic Berwald curvature, isotropic mean Berwald curvature, relatively isotropic Landsberg curvature, and relatively isotropic mean Landsberg curvature reduces to the Berwald metric, weakly Berwald metric, Landsberg metric, and weakly Landsberg metric, respectively. We also show that every generalized Kropina change of $m$th root Finsler metrics with almost vanishing $\textbf{H}$-curvature has vanishing $\textbf{H}$-curvature.


Evolution Equations With A Parameter And Application To Transport-Convection Differential Equations, Emile Franc Doungmo Goufo Jan 2017

Evolution Equations With A Parameter And Application To Transport-Convection Differential Equations, Emile Franc Doungmo Goufo

Turkish Journal of Mathematics

We deeply investigate the well-posedness of models taking the form $_0^AD^{\beta }_tu(t) = Au(t),\;\; u(0)= \,f,\;\;\;00$ where $_0^AD^{\beta }_t$ is a derivative with the fractional parameter $\beta$ and $A$ is a closed densely defined operator in a Banach space. We show that, unlike other systems, solutions of our models are not governed by Mittag--Leffler functions and their variants. We extend and adapt Peano's idea to our models and establish conditions for existence and uniqueness of solutions. In particular, relations between the two-parameter solution operator, its resolvent, and its generator are provided; the issue of subordination and prolongation principles are addressed; …