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Full-Text Articles in Physical Sciences and Mathematics

Some Sufficient Conditions For Starlikeness And Convexity, Mamoru Nunokawa, Shigeyoshi Owa, Yaşar Polatoğlu, Mert Çağlar, Emel Yavuz Duman Jan 2010

Some Sufficient Conditions For Starlikeness And Convexity, Mamoru Nunokawa, Shigeyoshi Owa, Yaşar Polatoğlu, Mert Çağlar, Emel Yavuz Duman

Turkish Journal of Mathematics

There are many results for sufficient conditions of functions f(z) which are analytic in the open unit disc U to be starlike and convex in U. In view of the results due to S. Ozaki, I. Ono and T. Umezawa (1956), P.T. Mocanu (1988), and M. Nunokawa (1993), some sufficient conditions for starlikeness and convexity of f(z) are discussed.


Injective Simplicial Maps Of The Arc Complex, Elmas Irmak, John D. Mccarthy Jan 2010

Injective Simplicial Maps Of The Arc Complex, Elmas Irmak, John D. Mccarthy

Turkish Journal of Mathematics

In this paper, we prove that each injective simplicial map of the arc complex of a compact, connected, orientable surface with nonempty boundary is induced by a homeomorphism of the surface. We deduce, from this result, that the group of automorphisms of the arc complex is naturally isomorphic to the extended mapping class group of the surface, provided the surface is not a disc, an annulus, a pair of pants, or a torus with one hole. We also show, for each of these special exceptions, that the group of automorphisms of the arc complex is naturally isomorphic to the quotient …


Some Properties Of C-Fusion Frames, Mohammad Hasan Faroughi, Reza Ahmadi Jan 2010

Some Properties Of C-Fusion Frames, Mohammad Hasan Faroughi, Reza Ahmadi

Turkish Journal of Mathematics

In [10], we generalized the concept of fusion frames, namely, c-fusion frames, which is a continuous version of the fusion frames. In this article we give some important properties about the generalization, namely erasures of subspaces, the bound of c-erasure reconstruction error for Parseval c-fusion frames, perturbation of c-fusion frames and the frame operator for fusion pair.


Notes On Null Curves In Minkowski Spaces, Makoto Sakaki Jan 2010

Notes On Null Curves In Minkowski Spaces, Makoto Sakaki

Turkish Journal of Mathematics

We show a correspondence between the evolute of a null curve and the involute of a certain spacelike curve in the 4-dimensional Minkowski space. Also we characterize pseudo-spherical null curves in the n-dimensional Minkowski space in terms of the curvature functions.


Warped Product Semi-Slant Submanifolds In Kenmotsu Manifolds, Mehmet Atçeken Jan 2010

Warped Product Semi-Slant Submanifolds In Kenmotsu Manifolds, Mehmet Atçeken

Turkish Journal of Mathematics

In this paper, we research the existence or non-existence of warped product semi-slant submanifolds in Kenmotsu manifolds. Consequently, we see that there are no proper warped product semi-slant submanifolds in Kenmotsu manifolds such that totally geodesic and totally umbilical submanifolds of warped product are proper semi-slant and invariant (or anti-invariant), respectively.


Generalized Catalan Numbers, Sequences And Polynomials, Cemal Koç, İsmai̇l Güloğlu, Songül Esi̇n Jan 2010

Generalized Catalan Numbers, Sequences And Polynomials, Cemal Koç, İsmai̇l Güloğlu, Songül Esi̇n

Turkish Journal of Mathematics

In this paper we present an algebraic interpretation for generalized Catalan numbers. We describe them as dimensions of certain subspaces of multilinear polynomials. This description is of utmost importance in the investigation of annihilators in exterior algebras.


Swan Conductors And Torsion In The Logarithmic De Rham Complex, Si̇nan Ünver Jan 2010

Swan Conductors And Torsion In The Logarithmic De Rham Complex, Si̇nan Ünver

Turkish Journal of Mathematics

We prove, for an arithmetic scheme X/S over a discrete valuation ring whose special fiber is a strict normal crossings divisor in X, that the Swan conductor of X/S is equal to the Euler characteristic of the torsion in the logarithmic de Rham complex of X/S. This is a precise logarithmic analog of a theorem by Bloch [1].


On Abelian Rings, Nazim Agayev, Abdullah Harmanci, Sai̇t Halicioğlu Jan 2010

On Abelian Rings, Nazim Agayev, Abdullah Harmanci, Sai̇t Halicioğlu

Turkish Journal of Mathematics

Let \alpha be an endomorphism of an arbitrary ring R with identity. In this note, we introduce the notion of \alpha-abelian rings which generalizes abelian rings. We prove that \alpha-reduced rings, \alpha-symmetric rings, \alpha-semicommutative rings and \alpha-Armendariz rings are \alpha-abelian. For a right principally projective ring R, we also prove that R is \alpha-reduced if and only if R is \alpha-symmetric if and only if R is \alpha-semicommutative if and only if R is \alpha-Armendariz if and only if R is \alpha-Armendariz of power series type if and only if R is \alpha-abelian.


Pseudo Simplicial Groups And Crossed Modules, İlker Akça, Sedat Pak Jan 2010

Pseudo Simplicial Groups And Crossed Modules, İlker Akça, Sedat Pak

Turkish Journal of Mathematics

In this paper, we define the notion of pseudo 2-crossed module and give a relation between the pseudo 2-crossed modules and pseudo simplicial groups with Moore complex of length 2.


On Construction Of Coherent States Associated With Homogeneous Spaces, Ali Akbar Arefijamaal Jan 2010

On Construction Of Coherent States Associated With Homogeneous Spaces, Ali Akbar Arefijamaal

Turkish Journal of Mathematics

In this article, assume that G=H\times_{\tau} K is the semidirect product of two locally compact groups H and K, respectively and consider the quasi regular representation on G. Then for some closed subgroups of G we investigate an admissible condition to generate the Gilmore-Perelomov coherent states. The construction yields a wide variety of coherent states, labelled by a homogeneous space of G.


Order-Isomorphism And A Projection's Diagram Of C(X), Ahmed S. Al-Rawashdeh, Sultan M. Al-Suleiman Jan 2010

Order-Isomorphism And A Projection's Diagram Of C(X), Ahmed S. Al-Rawashdeh, Sultan M. Al-Suleiman

Turkish Journal of Mathematics

A mapping between projections of C^*-algebras preserving the orthogonality, is called an orthoisomorphism. We define the order-isomorphism mapping on C^*-algebras, and using Dye's result, we prove in the case of commutative unital C^*-algebras that the concepts; order-isomorphism and the orthoisomorphism coincide. Also, we define the equipotence relation on the projections of C(X); indeed, new concepts of finiteness are introduced. The classes of projections are represented by constructing a special diagram, we study the relation between the diagram and the topological space X. We prove that an order-isomorphism, which preserves the equipotence of projections, induces a diagram-isomorphism; also if two diagrams …


The Essential Norm Of A Composition Operator On Orlicz Spaces, M. R. Jabbarzadeh Jan 2010

The Essential Norm Of A Composition Operator On Orlicz Spaces, M. R. Jabbarzadeh

Turkish Journal of Mathematics

In this note we determine the lower and upper estimates for the essential norm of a composition operator on the Orlicz spaces under certain conditions.


Transversal Lightlike Submanifolds Of Indefinite Sasakian Manifolds, Cumali̇ Yildirim, Bayram Şahi̇n Jan 2010

Transversal Lightlike Submanifolds Of Indefinite Sasakian Manifolds, Cumali̇ Yildirim, Bayram Şahi̇n

Turkish Journal of Mathematics

We study both radical transversal and transversal lightlike submanifolds of indefinite Sasakian manifolds. We give examples, investigate the geometry of distributions and obtain necessary and sufficient conditions for the induced connection on these submanifolds to be metric connection. We also study totally contact umbilical radical transversal and transversal lightlike submanifolds of indefinite Sasakian manifolds and obtain a classification theorem for totally contact umbilical transversal lightlike submanifolds.


Complete Systems Of Differential Invariants Of Vector Fields In A Euclidean Space, Djavvat Khadjiev Jan 2010

Complete Systems Of Differential Invariants Of Vector Fields In A Euclidean Space, Djavvat Khadjiev

Turkish Journal of Mathematics

The system of generators of the differential field of all G-invariant differential rational functions of a vector field in the n-dimensional Euclidean space R^n is described for groups G=M(n) and G=SM(n), where M(n) is the group of all isometries of R^n and SM(n) is the group of all euclidean motions of R^n. Using these results, vector field analogues of the first part of the Bonnet theorem for groups Aff(n), M(n), SM(n) in R^n are obtained, where Aff(n) is the group of all affine transformations of R^n. These analogues are given in terms of the first fundamental form and Christoffel symbols …


The Riemann Hilbert Problem For Generalized Q-Holomorphic Functions, Sezayi̇ Hizliyel, Mehmet Çağliyan Jan 2010

The Riemann Hilbert Problem For Generalized Q-Holomorphic Functions, Sezayi̇ Hizliyel, Mehmet Çağliyan

Turkish Journal of Mathematics

In this work, the classical Riemann Hilbert boundary value problem is extended to generalized Q-holomorphic functions.


Trace Formulae For Schrödinger Systems On Graphs, Chuan-Fu Yang, Zhen-You Huang, Xiao-Ping Yang Jan 2010

Trace Formulae For Schrödinger Systems On Graphs, Chuan-Fu Yang, Zhen-You Huang, Xiao-Ping Yang

Turkish Journal of Mathematics

For Schrödinger systems on metric graphs with \delta'-type conditions at the central vertex, firstly, we obtain precise description for the square root of the large eigenvalue up to the o(1/n)-term. Secondly, the regularized trace formulae for Schrödinger systems are calculated with some techniques in classical analysis. Finally, these formulae are used to obtain a result of inverse problem in the spirit of Ambarzumyan.


On The Codifferential Of The Kähler Form And Cosymplectic Metrics On Maximal Flag Manifolds, Marlio Paredes, Sofia Pinzon Jan 2010

On The Codifferential Of The Kähler Form And Cosymplectic Metrics On Maximal Flag Manifolds, Marlio Paredes, Sofia Pinzon

Turkish Journal of Mathematics

Using moving frames we obtain a formula to calculate the codifferential of the Kähler form on a maximal flag manifold. We use this formula to obtain some differential type conditions so that a metric on the classical maximal flag manifold be cosymplectic.


Generalized Fibonacci Sequences Related To The Extended Hecke Groups And An Application To The Extended Modular Group, Özden Koruoğlu, Recep Şahi̇n Jan 2010

Generalized Fibonacci Sequences Related To The Extended Hecke Groups And An Application To The Extended Modular Group, Özden Koruoğlu, Recep Şahi̇n

Turkish Journal of Mathematics

The extended Hecke groups \overline{H}(\lambda _{q}) are generated by T(z)=-1/z, S(z)=-1/(z+\lambda _{q}) and R(z)=1/ \overline{z} with \lambda _{q}=2\cos (\pi /q) for q\geq 3 integer. In this paper, we obtain a sequence which is a generalized version of the Fibonacci sequence given in [6] for the extended modular group \overline{\Gamma }, in the extended Hecke groups \overline{H}(\lambda_{q}). Then we apply our results to \overline{\Gamma } to find all elements of the extended modular group \overline{\Gamma }.


Traveling Wavefronts In A Single Species Model With Nonlocal Diffusion And Age-Structure, Xue-Shi Li, Guo Lin Jan 2010

Traveling Wavefronts In A Single Species Model With Nonlocal Diffusion And Age-Structure, Xue-Shi Li, Guo Lin

Turkish Journal of Mathematics

This paper is concerned with the existence of monotone traveling wavefronts in a single species model with nonlocal diffusion and age-structure. We first apply upper and lower solution technique to prove the result if the wave speed is larger than a threshold depending only on the basic parameters. When the wave speed equals to the threshold, we show the conclusion by passing to a limit function.


On Weakly M-Supplemented Primary Subgroups Of Finite Groups, Long Miao, Wolfgang Lempken Jan 2010

On Weakly M-Supplemented Primary Subgroups Of Finite Groups, Long Miao, Wolfgang Lempken

Turkish Journal of Mathematics

A subgroup H of a group G is said to be weakly M-supplemented in G if there exists a subgroup B of G provided that (1) G=HB, and (2) if H_1/H_G is a maximal subgroup of H/H_G, then H_1B=BH_1