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Full-Text Articles in Physical Sciences and Mathematics

Fiber Product Preserving Bundle Functors On Fibered-Fibered Manifolds, Wlodzimierz M. Mikulski Jan 2015

Fiber Product Preserving Bundle Functors On Fibered-Fibered Manifolds, Wlodzimierz M. Mikulski

Turkish Journal of Mathematics

We introduce the concept of modified vertical Weil functors on the category $\F_2\M_{m_1,m_2}$ of fibered-fibered manifolds with $(m_1,m_2)$-dimensional bases and their local fibered-fibered maps with local fibered diffeomorphisms as base maps. We then describe all fiber product preserving bundle functors on $\F_2\M_{m_1,m_2}$ in terms of modified vertical Weil functors.


On Condition $(Pwp)_{W}$ For $S$-Posets, Xingliang Liang, Yanfeng Luo Jan 2015

On Condition $(Pwp)_{W}$ For $S$-Posets, Xingliang Liang, Yanfeng Luo

Turkish Journal of Mathematics

Golchin and Rezaei (Commun Algebra 2009; 37: 1995--2007) introduced the weak version of Condition $(PWP)$ for $S$-posets, called Condition $(PWP)_{w}$. In this paper, we continue to study this condition. We first present a necessary and sufficient condition under which the $S$-poset $A(I)$ satisfies Condition $(PWP)_{w}$. Furthermore, we characterize pomonoids $S$ over which all cyclic (Rees factor) $S$-posets satisfy Condition $(PWP)_{w}$, and pomonoids $S$ over which all Rees factor $S$-posets satisfying Condition $(PWP)_{w}$ have a certain property. Finally, we consider direct products of $S$-posets satisfying Condition $(PWP)_{w}$.


On The Block Sequence Space $L_P(E)$ And Related Matrix Transformations, Davoud Foroutannia Jan 2015

On The Block Sequence Space $L_P(E)$ And Related Matrix Transformations, Davoud Foroutannia

Turkish Journal of Mathematics

The purpose of the present study is to introduce the sequence space $$l_p(E)=\left\{ x=(x_n)_{n=1}^{\infty}\;:\; \sum_{n=1}^{\infty} \left \sum_{j\in E_n}x_j\right ^p


Existence Of Unique Solution To Switchedfractional Differential Equations With $P$-Laplacian Operator, Xiufeng Guo Jan 2015

Existence Of Unique Solution To Switchedfractional Differential Equations With $P$-Laplacian Operator, Xiufeng Guo

Turkish Journal of Mathematics

In this paper, we study a class of nonlinear switched systems of fractional order with $p$-Laplacian operator. By applying a fixed point theorem for a concave operator on a cone, we obtain the existence and uniqueness of a positive solution for an integral boundary value problem with switched nonlinearity under some suitable assumptions. An illustrative example is included to show that the obtained results are effective.


Optimality Criteria For Sum Of Fractional Multiobjective Optimization Problem With Generalized Invexity, Deepak Bhati, Pitam Singh Jan 2015

Optimality Criteria For Sum Of Fractional Multiobjective Optimization Problem With Generalized Invexity, Deepak Bhati, Pitam Singh

Turkish Journal of Mathematics

The sum of a fractional program is a nonconvex optimization problem in the field of fractional programming and it is difficult to solve. The development of research is restricted to single objective sums of fractional problems only. The branch and bound methods/algorithms are developed in the literature for this problem as a single objective problem. The theoretical and algorithmic development for sums of fractional programming problems is restricted to single objective problems. In this paper, some new optimality conditions are proposed for the sum of a fractional multiobjective optimization problem with generalized invexity. The optimality conditions are obtained by using …


A Note On The Unit Distance Problem For Planar Configurations With $\Mathbb{Q}$-Independent Direction Set, Mark Herman, Jonathan Pakianathan Jan 2015

A Note On The Unit Distance Problem For Planar Configurations With $\Mathbb{Q}$-Independent Direction Set, Mark Herman, Jonathan Pakianathan

Turkish Journal of Mathematics

Let $T(n)$ denote the maximum number of unit distances that a set of $n$ points in the Euclidean plane $\mathbb{R}^2$ can determine with the additional condition that the distinct unit length directions determined by the configuration must be $\mathbb{Q}$-independent. This is related to the Erd\"os unit distance problem but with a simplifying additional assumption on the direction set that holds ``generically''. We show that $T(n+1)-T(n)$ is the Hamming weight of $n$, i.e. the number of nonzero binary coefficients in the binary expansion of $n$, and find a formula for $T(n)$ explicitly. In particular, $T(n)$ is $\Theta(n log(n))$. Furthermore, we describe …


On Metallic Riemannian Structures, Aydin Gezer, Çağri Karaman Jan 2015

On Metallic Riemannian Structures, Aydin Gezer, Çağri Karaman

Turkish Journal of Mathematics

The paper is devoted to the study of metallic Riemannian structures. An integrability condition and curvature properties for these structures by means of a $\Phi $-operator applied to pure tensor fields are presented. Examples of these structures are also given.


Moduli Spaces Of Arrangements Of 11 Projective Lines With A Quintuple Point, Meirav Amram, Cheng Gong, Mina Teicher, Wan-Yuan Xu Jan 2015

Moduli Spaces Of Arrangements Of 11 Projective Lines With A Quintuple Point, Meirav Amram, Cheng Gong, Mina Teicher, Wan-Yuan Xu

Turkish Journal of Mathematics

In this paper, we try to classify moduli spaces of arrangements of 11 lines with quintuple points. We show that moduli spaces of arrangements of 11 lines with quintuple points can consist of more than 2 connected components. We also present defining equations of the arrangements whose moduli spaces are not irreducible after taking quotients by the complex conjugation by Maple and supply some "potential Zariski pairs".


Bifurcation And Dynamics Of A Normal Form Map, Reza Khoshsiar Ghaziani Jan 2015

Bifurcation And Dynamics Of A Normal Form Map, Reza Khoshsiar Ghaziani

Turkish Journal of Mathematics

This paper investigates the dynamics and stability properties of a so-called planar truncated normal form map. This kind of map is widely used in the applied context, especially in normal form coefficients of n-dimensional maps. We determine analytically the border collision bifurcation curves that characterize the dynamic behaviors of the system. We first analyze stability of the fixed points and the existence of local bifurcations. Our analysis shows the presence of a rich variety of local bifurcations, namely stable fixed points, periodic cycles, quasiperiodic cycles that are constraints to stable attractors called invariant closed curves, and chaos, where dynamics of …


(X, Y)-Gorenstein Projective And Injective Modules, Qunxing Pan, Faqun Cai Jan 2015

(X, Y)-Gorenstein Projective And Injective Modules, Qunxing Pan, Faqun Cai

Turkish Journal of Mathematics

This paper introduces and studies (X,Y)-Gorenstein projective and injective modules, which are a generalization of Enochs' Gorenstein projective and injective modules, respectively. Our main aim is to investigate the relations among various (X,Y)-Gorenstein projective modules.


Balanced Pair Algorithm For A Class Of Cubic Substitutions, Tarek Sellami Jan 2015

Balanced Pair Algorithm For A Class Of Cubic Substitutions, Tarek Sellami

Turkish Journal of Mathematics

In this article we introduce the balanced pair algorithm associated with 2 unimodular Pisot substitutions having the same incidence matrix. We are interested in beta-substitution related to the polynomial x^3 - ax^2 - bx-1 for a \geq b \geq 1. Applying the balanced pair algorithm to these substitutions, we obtain a general formula for the associated intersection substitution.


Arithmetical Rank Of The Edge Ideals Of Some N-Cyclic Graphs With A Common Edge, Guangjun Zhu, Feng Shi, Yan Gu Jan 2015

Arithmetical Rank Of The Edge Ideals Of Some N-Cyclic Graphs With A Common Edge, Guangjun Zhu, Feng Shi, Yan Gu

Turkish Journal of Mathematics

In this paper, we present some lower bounds and upper bounds on the arithmetical rank of the edge ideals of some n-cyclic graphs with a common edge. For some special n-cyclic graphs with a common edge, we prove that the arithmetical rank equals the projective dimension of the corresponding quotient ring.


Zero Triple Product Determined Generalized Matrix Algebras, Dong Han Jan 2015

Zero Triple Product Determined Generalized Matrix Algebras, Dong Han

Turkish Journal of Mathematics

In this paper, we prove that the generalized matrix algebra G = \left[ A M N B \right] is a zero triple product (resp. zero Jordan triple product) determined if and only if A and B are zero triple products (resp. zero Jordan triple products) determined under certain conditions. Then the main results are applied to triangular algebras and full matrix algebras.


On Separating Subadditive Maps, Vesko Valov Jan 2015

On Separating Subadditive Maps, Vesko Valov

Turkish Journal of Mathematics

Recall that a map T \colon C(X,E) \to C(Y,F), where X, Y are Tychonoff spaces and E, F are normed spaces, is said to be separating, if for any 2 functions f,g \in C(X,E) we have c(T(f)) \cap c(T(g))= \varnothing provided c(f) \cap c(g) = \varnothing. Here c(f) is the co-zero set of f. A typical result generalizing the Banach--Stone theorem is of the following type (established by Araujo): if T is bijective and additive such that both T and T^{-1} are separating, then the realcompactification \nu X of X is homeomorphic to \nu Y. In this paper we show …


Coextended Weak Entwining Structures, José Nicanor Alonso Álvarez, José Manuel Fernandez Vilaboa, Ramón González Rodríguez Jan 2015

Coextended Weak Entwining Structures, José Nicanor Alonso Álvarez, José Manuel Fernandez Vilaboa, Ramón González Rodríguez

Turkish Journal of Mathematics

In this paper, we formulate the definition of coextended weak entwining structure in a strict monoidal category with equalizers. For a coextended weak entwining structure (A,D,\psi,\alpha), we introduce the notions of weak (D,\alpha)-cleft extension and weak (D,\alpha)-Galois extension (with normal basis), proving that weak (D,\alpha)-Galois extensions with normal basis are equivalent to weak (D,\alpha)-cleft extensions.


The Geometry Of Hemi-Slant Submanifolds Of A Locally Product Riemannian Manifold, Hakan Mete Taştan, Fatma Özdemi̇r Jan 2015

The Geometry Of Hemi-Slant Submanifolds Of A Locally Product Riemannian Manifold, Hakan Mete Taştan, Fatma Özdemi̇r

Turkish Journal of Mathematics

In the present paper, we study hemi-slant submanifolds of a locally product Riemannian manifold. We prove that the anti-invariant distribution involved in the definition of hemi-slant submanifold is integrable and give some applications of this result. We get a necessary and sufficient condition for a proper hemi-slant submanifold to be a hemi-slant product. We also study these types of submanifolds with parallel canonical structures. Moreover, we give two characterization theorems for the totally umbilical proper hemi-slant submanifolds. Finally, we obtain a basic inequality involving Ricci curvature and the squared mean curvature of a hemi-slant submanifold of a certain type of …


On Some Classes Of $3$-Dimensional Generalized $ (\Kappa ,\Mu )$-Contact Metric Manifolds, Ahmet Yildiz, Uday Chand De, Azi̇me Çeti̇nkaya Jan 2015

On Some Classes Of $3$-Dimensional Generalized $ (\Kappa ,\Mu )$-Contact Metric Manifolds, Ahmet Yildiz, Uday Chand De, Azi̇me Çeti̇nkaya

Turkish Journal of Mathematics

The object of the present paper is to obtain a necessary and sufficient condition for a $3$-dimensional generalized $(\kappa ,\mu )$-contact metric manifold to be locally $\phi $-symmetric in the sense of Takahashi and the condition is verified by an example. Next we characterize a $3$-dimensional generalized $(\kappa ,\mu )$-contact metric manifold satisfying certain curvature conditions on the concircular curvature tensor. Finally, we construct an example of a generalized $(\kappa,\mu)$-contact metric manifold to verify Theorem $1$ of our paper.


Stability In A Job Market With Linearly Increasing Valuations And Quota System, Yasir Ali Jan 2015

Stability In A Job Market With Linearly Increasing Valuations And Quota System, Yasir Ali

Turkish Journal of Mathematics

We consider a job market in which preferences of players are represented by linearly increasing valuations. The set of players is divided into two disjoint subsets: a set of workers and a set of firms. The set of workers is further divided into subsets, which represent different categories or classes in everyday life. We consider that firms have vacant posts for all such categories. Each worker wants a job for a category to which he/she belongs. Firms have freedom to hire more than one worker from any category. A worker can work in only one category for at most one …


Approximate Duals And Nearly Parseval Frames, Morteza Mirzaee Azandaryani Jan 2015

Approximate Duals And Nearly Parseval Frames, Morteza Mirzaee Azandaryani

Turkish Journal of Mathematics

In this paper we introduce approximate duality of g-frames in Hilbert $C^\ast$-modules and we show that approximate duals of g-frames in Hilbert $C^\ast$-modules share many useful properties with those in Hilbert spaces. Moreover, we obtain some new results for approximate duality of frames and g-frames in Hilbert spaces; in particular, we consider approximate duals of $\varepsilon$-nearly Parseval and $\varepsilon$-close frames.


Some Identities For The Glasser Transform And Their Applications, Faruk Uçar Jan 2015

Some Identities For The Glasser Transform And Their Applications, Faruk Uçar

Turkish Journal of Mathematics

In the present paper we consider a new integral transform, denoted by $\mathcal{G}_{\nu}$, which may be regarded as a generalization of the well-known transform due to Glasser. Many identities involving this transform are given. By making use of these identities, a number of new Parseval--Goldstein type identities are obtained for these and many other well-known integral transforms. The identities proven in this paper are shown to give rise to useful corollaries for evaluating infinite integrals of special functions. Some examples are also given as illustrations of the results presented here.


The Strong ``Zero-Two" Law For Positive Contractions Of Banach--Kantorovich $L_P$-Lattices, Inomjon Ganiev, Farrukh Mukhamedov, Dilmurod Bekbaev Jan 2015

The Strong ``Zero-Two" Law For Positive Contractions Of Banach--Kantorovich $L_P$-Lattices, Inomjon Ganiev, Farrukh Mukhamedov, Dilmurod Bekbaev

Turkish Journal of Mathematics

In the present paper we study dominated operators acting on Banach--Kantorovich $L_p$-lattices, constructed by a measure $m$ with values in the ring of all measurable functions. Using methods of measurable bundles of Banach--Kantorovich lattices, we prove the strong ``zero-two" law for positive contractions of Banach--Kantorovich $L_p$-lattices. \vspace{1mm}


On Isophote Curves And Their Characterizations, Fati̇h Doğan, Yusuf Yayli Jan 2015

On Isophote Curves And Their Characterizations, Fati̇h Doğan, Yusuf Yayli

Turkish Journal of Mathematics

An isophote curve comprises a locus of the surface points whose normal vectors make a constant angle with a fixed vector. The main objective of this paper is to find the axis of an isophote curve via its Darboux frame and afterwards to give some characterizations about the isophote curve and its axis in Euclidean 3-space. Particularly, for isophote curves lying on a canal surface other characterizations are obtained.


Jacobi-Spectral Method For Integro-Delay Differential Equations With Weakly Singular Kernels, Ishtiaq Ali Jan 2015

Jacobi-Spectral Method For Integro-Delay Differential Equations With Weakly Singular Kernels, Ishtiaq Ali

Turkish Journal of Mathematics

We present a numerical solution to the integro-delay differential equation with weakly singular kernels with the delay function $\theta (t)$ vanishing at the initial point of the given interval $[0, T]$ ($\theta (t) = qt, 0 < q < 1)$. In order to fully use the Jacobi orthogonal polynomial theory, we use some function and variable transformation to change the intergro-delay differential equation into a new equation defined on the standard interval $[-1, 1]$. A Gauss--Jacobi quadrature formula is used to evaluate the integral term. The spectral rate of convergence is provided in infinity norm under the assumption that the solution of the given equation is sufficiently smooth. For validation of the theoretical exponential rate of convergence of our method, we provide some numerical examples.


Planar Embedding Of Trees On Point Sets Without The General Position Assumption, Asghar Asgharian Sardroud, Alireza Bagheri Jan 2015

Planar Embedding Of Trees On Point Sets Without The General Position Assumption, Asghar Asgharian Sardroud, Alireza Bagheri

Turkish Journal of Mathematics

The problem of point-set embedding of a planar graph $G$ on a point set $P$ in the plane is defined as finding a straight-line planar drawing of $G$ such that the nodes of $G$ are mapped one to one on the points of $P$. Previous works in this area mostly assume that the points of $P$ are in general position, i.e. $P$ does not contain any three collinear points. However, in most of the real applications we cannot assume the general position assumption. In this paper, we show that deciding the point-set embeddability of trees without the general position assumption …


Generalized Chebyshev Polynomials Of The Second Kind, Mohammad A. Alqudah Jan 2015

Generalized Chebyshev Polynomials Of The Second Kind, Mohammad A. Alqudah

Turkish Journal of Mathematics

We characterize the generalized Chebyshev polynomials of the second kind (Chebyshev-II), and then we provide a closed form of the generalized Chebyshev-II polynomials using the Bernstein basis. These polynomials can be used to describe the approximation of continuous functions by Chebyshev interpolation and Chebyshev series and how to efficiently compute such approximations. We conclude the paper with some results concerning integrals of the generalized Chebyshev-II and Bernstein polynomials.


On The Classification Of Almost Null Rings, Ryszard Andruszkiewicz, Karol Pryszczepko Jan 2015

On The Classification Of Almost Null Rings, Ryszard Andruszkiewicz, Karol Pryszczepko

Turkish Journal of Mathematics

An almost null ring is a ring $R$ in which for all $a,b\in R$, $a^3=0$, $Ma^2=0$ for some square-free integer $M$ that depends on $a$ and $ab= ka^{2}=l b^{2}$ for some integers $k,l$. This paper is devoted to the classification of the almost null rings.


Magnetic Curves On Flat Para-K\"Ahler Manifolds, Mohamed Jleli, Marian Ioan Munteanu Jan 2015

Magnetic Curves On Flat Para-K\"Ahler Manifolds, Mohamed Jleli, Marian Ioan Munteanu

Turkish Journal of Mathematics

In this paper we prove that spacelike and timelike magnetic trajectories corresponding to the para-K\"ahler 2-form on a para-K\"ahler manifold $(M,\p,g)$ are circles on $M$. We then classify all para-K\"ahler magnetic curves in pseudo-Euclidean spaces ${\mathbb{E}}^{2n}_n$.


Approximation Properties Of Szász Type Operators Based On Charlier Polynomials, Arun Kajla, Purshottam Narain Agrawal Jan 2015

Approximation Properties Of Szász Type Operators Based On Charlier Polynomials, Arun Kajla, Purshottam Narain Agrawal

Turkish Journal of Mathematics

In the present paper, we study some approximation properties of the Sz\'{a}sz type operators involving Charlier polynomials introduced by Varma and Ta\c{s}delen in 2012. First, we establish approximation in a Lipschitz type space and weighted approximation theorems for these operators. Then we obtain the error in the approximation of functions having derivatives of bounded variation.


The Ext-Strongly Gorenstein Projective Modules, Jie Ren Jan 2015

The Ext-Strongly Gorenstein Projective Modules, Jie Ren

Turkish Journal of Mathematics

In this paper, we introduce and study Ext-strongly Gorenstein projective modules. We prove that the class of Ext-strongly Gorenstein projective modules is projective resolving. Moreover, we consider Ext-strongly Gorenstein projective precovers.


On Ampleness And Pseudo-Anosov Homeomorphisms In The Free Group, Rizos Sklinos Jan 2015

On Ampleness And Pseudo-Anosov Homeomorphisms In The Free Group, Rizos Sklinos

Turkish Journal of Mathematics

We use pseudo-Anosov homeomorphisms of surfaces in order to prove that the first-order theory of non-Abelian free groups, T_{fg}, is n-ample for any n \in \omega. This result adds to the work of Pillay, which proved that T_{fg} is non-CM-trivial. The sequence witnessing ampleness is a sequence of primitive elements in F_{\omega}. Our result provides an alternative proof to the main result of a recent preprint by Ould Houcine and Tent.