Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 40

Full-Text Articles in Physical Sciences and Mathematics

Some Properties Of The First Eigenvalue Of The $P(X)$-Laplacian On Riemannian Manifolds, R. A. Mashiyev, Guli̇zar Ali̇soy, Sezai̇ Ogras Jan 2009

Some Properties Of The First Eigenvalue Of The $P(X)$-Laplacian On Riemannian Manifolds, R. A. Mashiyev, Guli̇zar Ali̇soy, Sezai̇ Ogras

Turkish Journal of Mathematics

The main result of the present paper establishes a stability property of the first eigenvalue of the associated problem which deals with the $p(x)$-Laplacian on Riemannian manifolds with Dirichlet boundary condition.


Strong Convergence Theorems By An Extragradient Method For Solving Variational Inequalities And Equilibrium Problems In A Hilbert Space, Poom Kumam Jan 2009

Strong Convergence Theorems By An Extragradient Method For Solving Variational Inequalities And Equilibrium Problems In A Hilbert Space, Poom Kumam

Turkish Journal of Mathematics

In this paper, we introduce an iterative process for finding the common element of the set of fixed points of a nonexpansive mapping, the set of solutions of an equilibrium problem and the set of solutions of the variational inequality for monotone, Lipschitz-continuous mappings. The iterative process is based on the so-called extragradient method. We show that the sequence converges strongly to a common element of the above three sets under some parametric controlling conditions. This main theorem extends a recent result of Yao, Liou and Yao [Y. Yao, Y. C. Liou and J.-C. Yao, ''An Extragradient Method for Fixed …


Some Properties Of Gr-Multiplication Ideals, Hani Khashan Jan 2009

Some Properties Of Gr-Multiplication Ideals, Hani Khashan

Turkish Journal of Mathematics

In this paper, we study some of the properties of gr-multiplication ideals in a graded ring R. We first characterize finitely generated gr-multiplication ideals and then give a characterization of gr-multiplication ideals by using the gr-localization of R. Finally we determine the set of gr-P-primary ideals of R when P is a gr-multiplication gr-prime ideal of R.


Uniqueness For Meromorphic Functions And Differential Polynomials, Chao Meng Jan 2009

Uniqueness For Meromorphic Functions And Differential Polynomials, Chao Meng

Turkish Journal of Mathematics

In this article, we deal with the uniqueness problems on meromorphic functions concerning differential polynomials and prove the following result: Let f and g be two transcendental meromorphic functions, \alpha be a meromorphic function such that T(r,\alpha)=o(T(r,f)+T(r,g)) and \alpha \not\equiv 0,\infty. Let a be a nonzero constant. Suppose that m,n are positive integers such that n>m+10. If \Psi_f' and \Psi_g' share ``(0,2)", then (i) if m\geq 2, then f(z)\equiv g(z); (ii) if m=1, either f(z)\equiv g(z) or f and g satisfy the algebraic equation R(f,g)\equiv 0, where R(\varpi_1,\varpi_2)=(n+1)(\varpi_1^{n+2}-\varpi_2^{n+2})-(n+2)(\varpi_1^{n+1} -\varpi_2^{n+1}). The results in this paper improve the results of Xiong-Lin-Mori …


Intrinsic Equations For A Generalized Relaxed Elastic Line On An Oriented Surface In The Minkowski 3-Space E_1^3, Cumali̇ Eki̇ci̇, Ali̇ Görgülü Jan 2009

Intrinsic Equations For A Generalized Relaxed Elastic Line On An Oriented Surface In The Minkowski 3-Space E_1^3, Cumali̇ Eki̇ci̇, Ali̇ Görgülü

Turkish Journal of Mathematics

H. K. Nickerson and Gerald S. Manning [8] derived the intrinsic equations for a relaxed elastic line on an oriented surface in the Euclidean 3-dimensional space E^3. In this paper, we define a generalized relaxed elastic line and derive the intrinsic equations for a generalized of relaxed elastic line on an oriented surface in the Minkowski 3-dimensional space E_1^3 and give some applications of the result.


Stack-Sortable Permutations And Polynomials, İsmai̇l Ş. Güloğlu, Cemal Koç Jan 2009

Stack-Sortable Permutations And Polynomials, İsmai̇l Ş. Güloğlu, Cemal Koç

Turkish Journal of Mathematics

The Catalan numbers show up in a diverse variety of counting problems. In this note we give yet another characterization of the Catalan number C(n). It is characterized as the dimension of a certain space of multilinear polynomials by exhibiting a basis.


On \Phi-Recurrent Kenmotsu Manifolds, Uday Chand De, Ahmet Yildiz, Funda Yaliniz Jan 2009

On \Phi-Recurrent Kenmotsu Manifolds, Uday Chand De, Ahmet Yildiz, Funda Yaliniz

Turkish Journal of Mathematics

The object of this paper is to study \phi-recurrent Kenmotsu manifolds. Also three-dimensional locally \phi-recurrent Kenmotsu manifolds have been considered. Among others it is proved that a locally \phi-recurrent Kenmotsu spacetime is the Robertson-Walker spacetime. Finally we give a concrete example of a three-dimensional Kenmotsu manifold.


Multiple Positive Solutions For Nonlinear Third-Order Boundary Value Problems In Banach Spaces, Feng Wang, Hai-Hua Lu, Fang Zhang Jan 2009

Multiple Positive Solutions For Nonlinear Third-Order Boundary Value Problems In Banach Spaces, Feng Wang, Hai-Hua Lu, Fang Zhang

Turkish Journal of Mathematics

This paper deals with the positive solutions of nonlinear boundary value problems in Banach spaces. By using fixed point index theory, some sufficient conditions for the existence of at least one or two positive solutions to boundary value problems in Banach spaces are obtained. An example illustrating the main results is given.


Cartan Calculus On The Quantum Space R_Q^3, Sali̇h Çeli̇k, E. Mehmet Özkan, Ergün Yaşar Jan 2009

Cartan Calculus On The Quantum Space R_Q^3, Sali̇h Çeli̇k, E. Mehmet Özkan, Ergün Yaşar

Turkish Journal of Mathematics

To give a Cartan calculus on the extended quantum 3d space, the noncommutative differential calculus on the extended quantum 3d space is extended by introducing inner derivations and Lie derivatives.


Oscillation Of Higher-Order Nonlinear Delay Differential Equations With Oscillatory Coefficients, Başak Karpuz, Özkan Öcalan, Mustafa Kemal Yildiz Jan 2009

Oscillation Of Higher-Order Nonlinear Delay Differential Equations With Oscillatory Coefficients, Başak Karpuz, Özkan Öcalan, Mustafa Kemal Yildiz

Turkish Journal of Mathematics

A criterion is established on the bounded solutions of type higher-order nonlinear neutral differential equations of type oscillatory or tending to zero at infinity [a(t) [x(t)+r(t)x(\kappa(t))]^{(n-1]' +p(t)F(x(\tau(t)))+q(t)G(x(\sigma(t)))= \phi(t), where t\geq t_0, n\geq 2, a,p are positive, r,q,\phi are allowed to alternate in sign infinitely many times, F,G are continuous functions, and \kappa,\tau,\sigma are strictly increasing unbounded continuous delay functions.


Approximation By Certain Linear Operators Preserving X^2, Lucyna Rempulska, Karolina Tomczak Jan 2009

Approximation By Certain Linear Operators Preserving X^2, Lucyna Rempulska, Karolina Tomczak

Turkish Journal of Mathematics

We investigate certain positive linear operators L_n preserving the functions e_k (x)=x^k, k=0, 1, and modified operators L_n^* which preserve e_0 and e_2. We show that the error of approximation of f by L_n^* (f) is smaller than for L_n(f).


Integral And Homothetic Indecomposability With Applications To Irreducibility Of Polynomials, Fati̇h Koyuncu, Ferruh Özbudak Jan 2009

Integral And Homothetic Indecomposability With Applications To Irreducibility Of Polynomials, Fati̇h Koyuncu, Ferruh Özbudak

Turkish Journal of Mathematics

Being motivated by some methods for construction of homothetically indecomposable polytopes, we obtain new methods for construction of families of integrally indecomposable polytopes. As a result, we find new infinite families of absolutely irreducible multivariate polynomials over any field F. Moreover, we provide different proofs of some of the main results of Gao [2].


On Completeness Of Elementary Generalized Solutions Of A Class Of Operator-Differential Equations Of A Higher Order, Rovshan Z. Gumbataliev Jan 2009

On Completeness Of Elementary Generalized Solutions Of A Class Of Operator-Differential Equations Of A Higher Order, Rovshan Z. Gumbataliev

Turkish Journal of Mathematics

In this paper we give definition of m-fold completeness and prove a theorem on completeness of elementary generalized solution of corresponding boundary value problems at which the equation describes the process of corrosive fracture of metals in aggressive media and the principal part of the equation has multiple characteristics.


Existence And Uniqueness Theorem For Slant Immersions In Kenmotsu Space Forms, Pradeep Kumar Pandey, Ram Shankar Gupta Jan 2009

Existence And Uniqueness Theorem For Slant Immersions In Kenmotsu Space Forms, Pradeep Kumar Pandey, Ram Shankar Gupta

Turkish Journal of Mathematics

In this paper we have obtained a general existence as well as uniqueness theorem for slant immersions into a Kenmotsu-space form.


Korovkin Type Error Estimates For Positive Linear Operators Involving Some Special Functions, Ogün Doğru, Esra Erkuş-Duman Jan 2009

Korovkin Type Error Estimates For Positive Linear Operators Involving Some Special Functions, Ogün Doğru, Esra Erkuş-Duman

Turkish Journal of Mathematics

In the present paper, we introduce a new sequence of linear positive operators with the help of generating functions. We obtain some Korovkin type approximation properties for these operators and compute rates of convergence by means of the first and second order modulus of continuities and Peetre´s K-functional. In order to obtain explicit expressions for the first and second moment of our operators, we obtain a functional differential equation including our operators. Furthermore, we deal with a modification of our operators converging to integral of function f on the interval (0,1).


Geodesics Of The Cheeger-Gromoll Metric, Ari̇f A. Salimov, S. Kazimova Jan 2009

Geodesics Of The Cheeger-Gromoll Metric, Ari̇f A. Salimov, S. Kazimova

Turkish Journal of Mathematics

The main purpose of the paper is to investigate geodesics on the tangent bundle with respect to the Cheeger-Gromoll metric.


On Symmetric Monomial Curves In P^3, Mesut Şahi̇n Jan 2009

On Symmetric Monomial Curves In P^3, Mesut Şahi̇n

Turkish Journal of Mathematics

In this paper, we give an elementary proof of the fact that symmetric arithmetically Cohen-Macaulay monomial curves are set-theoretic complete intersections. The proof is constructive and provides the equations of the surfaces cutting out the monomial curve.


Modules With Unique Closure Relative To A Torsion Theory Ii, Semra Doğruöz, Abdullah Harmanci, Patrick F. Smith Jan 2009

Modules With Unique Closure Relative To A Torsion Theory Ii, Semra Doğruöz, Abdullah Harmanci, Patrick F. Smith

Turkish Journal of Mathematics

We study modules M over a general ring R such that every submodule has a unique closure with respect to a hereditary torsion theory \tau on Mod-R using the fact that the module M satisfies a certain transitivity property on \tau-closed submodules.


The Existence Of Triple Positive Solutions Of Nonlinear Four-Point Boundary Value Problem With P-Laplacian, Xiang-Feng Li, Pei-Hao Zhao Jan 2009

The Existence Of Triple Positive Solutions Of Nonlinear Four-Point Boundary Value Problem With P-Laplacian, Xiang-Feng Li, Pei-Hao Zhao

Turkish Journal of Mathematics

This paper deals with the multiplicity results of positive solutions of one-dimensional singular p-Laplace equation (\varphi_p(u'(t)))'+a(t)f(t,u(t),u'(t))=0, 0


Modified Szász-Mirakjan-Kantorovich Operators Preserving Linear Functions, Oktay Duman, Mehmet Ali̇ Özarslan, Biancamaria Della Vecchia Jan 2009

Modified Szász-Mirakjan-Kantorovich Operators Preserving Linear Functions, Oktay Duman, Mehmet Ali̇ Özarslan, Biancamaria Della Vecchia

Turkish Journal of Mathematics

In this paper, we introduce a modification of the Szász-Mirakjan-Kantorovich operators, which preserve the linear functions. This type of operator modification enables better error estimation on the interval [1/2,+\infty) than the classical Szász-Mirakjan-Kantorovich operators. We also obtain a Voronovskaya-type theorem for these operators.


Equi-Statistical Extension Of The Korovkin Type Approximation Theorem, Sevda Karakuş, Kami̇l Demi̇rci̇ Jan 2009

Equi-Statistical Extension Of The Korovkin Type Approximation Theorem, Sevda Karakuş, Kami̇l Demi̇rci̇

Turkish Journal of Mathematics

In this paper using equi-statistical convergence, which is stronger than the usual uniform convergence and statistical uniform convergence, we obtain a general Korovkin type theorem. Then, we construct examples such that our new approximation result works but its classical and statistical cases do not work.


A New Approach On Constant Angle Surfaces In E^3, Marian Ioan Munteanu, Ana Irina Nistor Jan 2009

A New Approach On Constant Angle Surfaces In E^3, Marian Ioan Munteanu, Ana Irina Nistor

Turkish Journal of Mathematics

In this paper we study constant angle surfaces in Euclidean 3--space. Even that the result is a consequence of some classical results involving the Gauss map (of the surface), we give another approach to classify all surfaces for which the unit normal makes a constant angle with a fixed direction.


Local Fourier Bases And Ultramodulation Spaces, Salti Samarah, Fady Hasan Jan 2009

Local Fourier Bases And Ultramodulation Spaces, Salti Samarah, Fady Hasan

Turkish Journal of Mathematics

It was proved that local Fourier bases are unconditional bases for modulation spaces M_{p.q}^w. We prove that the local Fourier bases are unconditional bases for ultramodulation spaces M_p^{w_{\gamma}}=M_{p.p}^{w_{\gamma}}, where 0


Q-Modules, C. Jayaram, Ünsal Teki̇r Jan 2009

Q-Modules, C. Jayaram, Ünsal Teki̇r

Turkish Journal of Mathematics

In this paper we characterize Q-modules and almost Q-modules. Next we estblish some equivalent conditions for an almost Q-module to be a Q-module. Using these results, some characterizations are given for Noetherian Q-modules.


Criteria Of Nilpotency And Influence Of Contranormal Subgroups On The Structure Of Infinite Groups, Leonid Andreevich Kurdachenko, Javier Otal, Igor Yakov Subbotin Jan 2009

Criteria Of Nilpotency And Influence Of Contranormal Subgroups On The Structure Of Infinite Groups, Leonid Andreevich Kurdachenko, Javier Otal, Igor Yakov Subbotin

Turkish Journal of Mathematics

Following J.S. Rose, a subgroup H of a group G is called contranormal if G=H^G. In a certain sense, contranormal subgroups are antipodes to subnormal subgroups. It is well known that a finite group is nilpotent if and only if it has no proper contranormal subgroups. However, for infinite groups this criterion is not valid. There are examples of non-nilpotent infinite groups whose subgroups are subnormal; in particular, these groups have no contranormal subgroups. Nevertheless, for some classes of infinite groups, the absence of contranormal subgroups implies nilpotency of the group. The present article is devoted to the search of …


Some Inequalities Concerning The Rate Of Growth Of Polynomials, Abdullah Mir, K. K. Dewan, Naresh Singh Jan 2009

Some Inequalities Concerning The Rate Of Growth Of Polynomials, Abdullah Mir, K. K. Dewan, Naresh Singh

Turkish Journal of Mathematics

In this paper we consider a class of polynomials p(z)=a_0+\suml_{v=t}^n a_vz^v, t\ge1, not vanishing in z


Strong Differential Subordination, Georgia Irina Oros, Gheorghe Oros Jan 2009

Strong Differential Subordination, Georgia Irina Oros, Gheorghe Oros

Turkish Journal of Mathematics

The concept of differential subordination was introduced in [4] by S. S. Miller and P. T. Mocanu and the concept of strong differential subordination was introduced in [1] by J. A. Antonino and S. Romaguera. This last concept was applied in the special case of Briot-Bouquet strong differential subordination. In this paper we study the strong differential subordinations in the general case, following the general theory of differential subordinations presented in [4].


Partial Open Book Decompositions And The Contact Class In Sutured Floer Homology, Tolga Etgü, Burak Özbağci Jan 2009

Partial Open Book Decompositions And The Contact Class In Sutured Floer Homology, Tolga Etgü, Burak Özbağci

Turkish Journal of Mathematics

We demonstrate how to combinatorially calculate the EH-class of a compatible contact structure in the sutured Floer homology group of a balanced sutured three manifold which is associated to an abstract partial open book decomposition. As an application we show that every contact three manifold (closed or with convex boundary) can be obtained by gluing tight contact handlebodies whose EH-classes are nontrivial.


C1 Modules With Respect To A Hereditary Torsion Theory, Tahi̇re Özen Jan 2009

C1 Modules With Respect To A Hereditary Torsion Theory, Tahi̇re Özen

Turkish Journal of Mathematics

An R-module M is said to be a C1-module if every closed submodule of M is a direct summand. In this paper we introduce and investigate the concept of the \tau-C1 module for a hereditary torsion theory \tau on Mod-R. \tau-C1 modules are a generalization of C1-modules.


A Perturbation Of M-Order Derivations On Banach Algebras, Yong-Soo Jung, Kyoo-Hong Park Jan 2009

A Perturbation Of M-Order Derivations On Banach Algebras, Yong-Soo Jung, Kyoo-Hong Park

Turkish Journal of Mathematics

Let \A be a unital Banach algebra and let m, 1 \leq m \leq 4, be an integer. If f: \A \to \A is an approximate m-order derivation in the sense of Hyers-Ulam-Rassias, then f: \A \to \A is an exact m-order derivation.