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Full-Text Articles in Physical Sciences and Mathematics

On Some Class Of Hypersurfaces In \Bbb{E}^{N+1} Satisfying Chen's Equality, Ci̇han Özgür, Kadri̇ Arslan Jan 2002

On Some Class Of Hypersurfaces In \Bbb{E}^{N+1} Satisfying Chen's Equality, Ci̇han Özgür, Kadri̇ Arslan

Turkish Journal of Mathematics

In this paper we study pseudosymmetry type hypersurfaces in the Euclidean space \Bbb{E}^{n+1} satisfying B. Y. Chen's equality.


On The Modular Curve X(6) And Surfaces Admitting Genus 2 Fibrations, Gülay Karadoğan Jan 2002

On The Modular Curve X(6) And Surfaces Admitting Genus 2 Fibrations, Gülay Karadoğan

Turkish Journal of Mathematics

In this paper, we study the moduli spaces of surfaces admitting nonsmooth genus 2 fibrations with slope \lambda = 6 (necessarily) over curves of genus \geq 1. We determine the structure of each connected component of these moduli spaces. Our results fill the gap of earlier work in the literature to complete the picture of the moduli spaces of genus 2 fibrations over curves of genus \geq 2 except for the case of \lambda = 4.


On Derivations Of Prime Gamma Rings, Mehmet Ali̇ Öztürk, Young Bae Jun, Kyung Ho Kim Jan 2002

On Derivations Of Prime Gamma Rings, Mehmet Ali̇ Öztürk, Young Bae Jun, Kyung Ho Kim

Turkish Journal of Mathematics

We consider some results in a \Gamma-ring M with derivation which is related to Q, and the quotient \Gamma-ring of M.


On Locally Pre-C^{*}-Algebra Structures In Locally M-Convex H^{*}-Algebras, A. El-Kinani Jan 2002

On Locally Pre-C^{*}-Algebra Structures In Locally M-Convex H^{*}-Algebras, A. El-Kinani

Turkish Journal of Mathematics

We endow any locally m-convex H^{*}-algebra \left( E,\tau \right) with a locally pre-C^{*}-topology weaker than \tau. Examples and applications are provided.


Flat Marcinkiewicz Integral Operators, Hussain Al-Qassem, Ahmad Al-Salman Jan 2002

Flat Marcinkiewicz Integral Operators, Hussain Al-Qassem, Ahmad Al-Salman

Turkish Journal of Mathematics

In this paper, we study Marcinkiewicz integral operators with rough kernels supported by surfaces of revolutions. We prove that our operators are bounded on L^p under certain convexity assumptions on our surfaces and under very weak conditions on the kernel.


Solving Fuzzy Linear Programming Problems With Linear Membership Function, Rafail R. Gasimov, Kürşat Yeni̇lmez Jan 2002

Solving Fuzzy Linear Programming Problems With Linear Membership Function, Rafail R. Gasimov, Kürşat Yeni̇lmez

Turkish Journal of Mathematics

In this paper, we concentrate on two kinds of fuzzy linear programming problems: linear programming problems with only fuzzy technological coefficients and linear programming problems in which both the right-hand side and the technological coefficients are fuzzy numbers. We consider here only the case of fuzzy numbers with linear membership functions. The symmetric method of Bellman and Zadeh [2] is used for a defuzzification of these problems. The crisp problems obtained after the defuzzification are non-linear and even non-convex in general. We propose here the ``modified subgradient method'' and use it for solving these problems. We also compare the new …


One Sided Banach Algebras, A. El Kinani, A. Najmi, Mohamed Oudadess Jan 2002

One Sided Banach Algebras, A. El Kinani, A. Najmi, Mohamed Oudadess

Turkish Journal of Mathematics

Many properties of two-sided algebras remain valid for one-sided algebras. Namely, any one sided Banach algebra is commutative modulo its Jacobson radical.


On Some Properties Connecting Infinite Series, B. K. Lahiri, Pratulananda Das Jan 2002

On Some Properties Connecting Infinite Series, B. K. Lahiri, Pratulananda Das

Turkish Journal of Mathematics

We prove several theorems connecting infinite series of real terms in relation to Borel and Baire classification of sets and functions, connectedness of mappings, porosity character of sets etc.


On The Spectral Properties Of The Regular Sturm-Liouville Problem With The Lag Argument For Which Its Boundary Conditions Depends On The Spectral Parameter, Mehmet Bayramoğlu, Kevser Özden Köklü, Oya Baykal Jan 2002

On The Spectral Properties Of The Regular Sturm-Liouville Problem With The Lag Argument For Which Its Boundary Conditions Depends On The Spectral Parameter, Mehmet Bayramoğlu, Kevser Özden Köklü, Oya Baykal

Turkish Journal of Mathematics

In this paper, the asymptotic expression of the eigenvalues and eigenfunctions of the Sturm-Liouville equation with the lag argument y''(t) + \lambda^2 y(t) + M(t)y (t - \Delta(t)) = 0 and the spectral parameter in the boundary conditions \lambda y(0) +y'(0) = 0 \lambda^{2}y(\pi) + y'(\pi) = 0 y(t - \Delta(t)) = y(0)\varphi(t - \Delta(t)), t - \Delta(t) < 0 has been founded in a finite interval, where M(t) and \Delta(t) \geq 0 are continuous functions on [0, \pi], \lambda > 0 is a real parameter, \varphi(t) is an initial function which is satisfied with the condition \varphi(0) = 1 and continuous in the initial set.


A Class Of Monoids Embeddable In A Group, Ebru Keyman Jan 2001

A Class Of Monoids Embeddable In A Group, Ebru Keyman

Turkish Journal of Mathematics

In this paper, we develop a new method to show that a monoid, given by a certain kind of presentation, embeds in a group. A mathematical device called the diamond condition was used in [5] to prove that the singular braid monoid SB_n embeds. Motivated by this, we consider monoid presentations which have the basic properties of the presentation of the singular braid monoid. In the same way as in [5], we prove that the monoid embeds. The proof of the diamond condition is completely geometric in [5], but here we prove it by using elementary algebraic properties.


Symplectic Maps To Projective Spaces And Symplectic Invariants, Denis Auroux Jan 2001

Symplectic Maps To Projective Spaces And Symplectic Invariants, Denis Auroux

Turkish Journal of Mathematics

After reviewing recent results on symplectic Lefschetz pencils and symplectic branched covers of \CP^2, we describe a new construction of maps from symplectic manifolds of any dimension to \CP^2 and the associated monodromy invariants. We also show that a dimensional induction process makes it possible to describe any compact symplectic manifold by a series of words in braid groups and a word in a symmetric group.


The Topology Of Symplectic Manifolds, Robert E. Gompf Jan 2001

The Topology Of Symplectic Manifolds, Robert E. Gompf

Turkish Journal of Mathematics

A topological structure is introduced that seems likely to provide a complete topological characterization of compact symplectic manifolds. The article begins with a leisurely introduction to symplectic manifolds from a topological viewpoint. It then focuses on Thurston's construction of a symplectic structure on the total space of a fiber bundle. This is generalized to a technique for putting a symplectic structure on the domain of a J-holomorphic map. A topological structure called a hyperpencil on a compact 2n-manifold is then defined; this is motivated by the special case of a linear system of curves on an algebraic manifold, and it …


Surface Bundles: Some Interesting Examples, Jim Bryan, Ron Donagi, Andras I. Stipsicz Jan 2001

Surface Bundles: Some Interesting Examples, Jim Bryan, Ron Donagi, Andras I. Stipsicz

Turkish Journal of Mathematics

We show two constructions of surface bundles over Riemann surfaces admitting nonvanishing signatures.


Torus Fibrations On Symplectic Four-Manifolds, Ivan Smith Jan 2001

Torus Fibrations On Symplectic Four-Manifolds, Ivan Smith

Turkish Journal of Mathematics

This paper has two essentially unrelated halves. In the first we prove that a closed symplectic four-manifold admitting a fibration by connected, homologically essential Lagrangian tori with "tame" singularities, is fibre-preserving diffeomorphic to a K3 surface or to a torus bundle over a torus with first Betti number at least three. In the second, we prove that these torus bundles over tori admit Lefschetz pencils by genus three curves. It follows that the genus three mapping class group admits infinitely many inequivalent irreducible positive relations. Motivations for the questions are provided from mirror symmetry, integrable systems and Seiberg-Witten theory: in …


Floer Homology And Its Continuity For Non-Compact Lagrangian Submanifolds, Yong-Geum Oh Jan 2001

Floer Homology And Its Continuity For Non-Compact Lagrangian Submanifolds, Yong-Geum Oh

Turkish Journal of Mathematics

We give a construction of the Floer homology of the pair of vnon-compact Lagrangian submanifolds, which satisfies natural continuity property under the Hamiltonian isotopy that moves the infinity but leaves the intersection set of the pair compact. This construction uses the concept of Lagrangian cobordism and certain singular Lagrangian submanifolds. We apply this construction to conormal bundles (or varieties) in the cotangent bundle, and relate it to a conjecture made by MacPherson on the intersection theory of the characteristic Lagrangian cycles associated to the perverse sheaves constructible to a complex stratification on the complex algebraic manifold.


A Partial Order On The Group Of Contactomorphisms Of $\R^{2n+1}$ Via Generating Functions, Mohan Bhupal Jan 2001

A Partial Order On The Group Of Contactomorphisms Of $\R^{2n+1}$ Via Generating Functions, Mohan Bhupal

Turkish Journal of Mathematics

In this note we construct a nontrivial partial order on the identity component of the group of compactly supported contactomorphisms of \R^{2n+1} using the method of generating functions. Our construction is in the framework of the theory developed by Viterbo in the paper \cite{V} wherein, among other things, he showed how one could use generating functions to construct a partial order on the group of compactly supported Hamiltonian symplectomorphisms of \R^{2n}.


Knotting Of Algebraic Curves In Complex Surfaces, Sergey Finashin Jan 2001

Knotting Of Algebraic Curves In Complex Surfaces, Sergey Finashin

Turkish Journal of Mathematics

For any d\ge 5, I constructed infinitely many pairwise smoothly non-equivalent surfaces F\subset\Cp{2} homeomorphic to a non-singular algebraic curve of degree d, realizing the same homology class as such a curve and having abelian fundamental group \pi_1(\Cp2\stmin F). It is a special case of a more general theorem, which concerns for instance those algebraic curves, A, in a simply connected algebraic surface, X, which admit irreducible degenerations to a curve A_0, with a unique singularity of the type X_9, and such that A\cite A>16.


Topological Quantum Field Theory And Hyperkähler Geometry, Justin Sawon Jan 2001

Topological Quantum Field Theory And Hyperkähler Geometry, Justin Sawon

Turkish Journal of Mathematics

Rozansky and Witten proposed a 3-dimensional sigma-model whose target space is a hyperkähler manifold. They conjectured that this theory has an associated TQFT, with vector spaces given by certain cohomology groups of the hyperkähler manifold. On the other hand, there is a certain modified TQFT constructed by Murakami and Ohtsuki using the universal quantum invariant. We explain how the Rozansky-Witten TQFT can be obtained from the latter by applying a "hyperkähler weight system".


Induced Cat^1-Groups, Murat Alp Jan 2001

Induced Cat^1-Groups, Murat Alp

Turkish Journal of Mathematics

In this paper we define the pullback cat^1-group and show that this Pullback has a right adjoint which is the induced cat^1-group. Later we show that this right adjoint is a pushout of category of cat^1-groups. We calculate the Peiffer subgroups to find a finite group of the source of induced cat^1-groups. The generating set of Peiffer subgroups are also given in this paper. All results are corrected by a GAP[13] program package in [4]. This paper also contains the some computational examples which are the calculation-induced cat^1-group and comparative times between the induced crossed modules and induced cat^1-groups.


P -Banach Algebras With Generalized Involution And C^*-Algebra Structure, Abdellah El Kinani, Aziz Ifzarne, Mohamed Oudadess Jan 2001

P -Banach Algebras With Generalized Involution And C^*-Algebra Structure, Abdellah El Kinani, Aziz Ifzarne, Mohamed Oudadess

Turkish Journal of Mathematics

In this paper, we consider p-Banach algebras endowed with a generalized involution. We show that various C^*-like conditions force the algebra to be C^*-algebra under an equivalent norm.


Inequalities For The Vibrating Clamped Plate Problem, Kimberley Mchale, Ünal Ufuktepe Jan 2001

Inequalities For The Vibrating Clamped Plate Problem, Kimberley Mchale, Ünal Ufuktepe

Turkish Journal of Mathematics

We study the eigenvalues of the vibrating clamped plate problem. We have made improvements on the bounds of the ratios of the eigenvalues of the biharmonic operator (clamped plate) using the methods of Payne, Polya, and Weinberger. The difference in our proof lies mainly with the trial functions and the orthogonality arguments. While Payne, Polya, and Weinberger and Hile and Yeh project away components along u_1,u_2,...,u_k to meet the orthogonality conditions,we use a translation/rotation argument to meet these conditions.


A Perturbed Version Of The Ostrowski Inequality For Twice Differentiable Mappings, A. Sofo, S. S. Dragomir Jan 2001

A Perturbed Version Of The Ostrowski Inequality For Twice Differentiable Mappings, A. Sofo, S. S. Dragomir

Turkish Journal of Mathematics

A generalisation of a perturbed version of the Ostrowski inequality for twice differentiable mappings is studied. It is shown that the error bounds are better than those obtained previously. Applications for general quadrature formulae are also given.


On The L^P Solutions Of Dilation Equations, İbrahi̇m Kirat Jan 2001

On The L^P Solutions Of Dilation Equations, İbrahi̇m Kirat

Turkish Journal of Mathematics

In this paper, the concepts concerning the space of constant breadth were extended to E^n-space. An approximate solution of the equation system which belongs to this curve was obtained. Using this solution vectorial expression of the curves of constant breadth was obtained. The relation \int_0^{2\pi}\widetilde{f}(s)\,ds=0 between the curvatures of curves of constant breadth in E^n was obtained. Key Words and Phrases: Curvature, Constant Breadth, Integral Characterization of Curve"> MathJax.Hub.Config({tex2jax: {inlineMath: [['$','$'], ['\\(','\\)']], displayMath: [['\\[','\\]'], ['$$','$$']]}}); Academic Journals Find Manuscript Copyright Release Form Copyright Release Form(Turkey) Copyright Release Form(Other Countries) Manuscript Submission and Evaluation System On the L^p Solutions of Dilation …


Some Characterization Of Curves Of Constant Breadth In E^N Space, Zülfi̇gar Akdoğan, Abdullah Mağden Jan 2001

Some Characterization Of Curves Of Constant Breadth In E^N Space, Zülfi̇gar Akdoğan, Abdullah Mağden

Turkish Journal of Mathematics

In this paper, the concepts concerning the space of constant breadth were extended to E^n-space. An approximate solution of the equation system which belongs to this curve was obtained. Using this solution vectorial expression of the curves of constant breadth was obtained. The relation \int_0^{2\pi}\widetilde{f}(s)ds=0 between the curvatures of curves of constant breadth in E^n was obtained. Key Words and Phrases: Curvature, Constant Breadth, Integral Characterization of Curve


Fuzzy Maximal Ideals Of Gamma Near-Rings, Young Bae Yun, Kyung Ho Kim, Mehmet Ali̇ Öztürk Jan 2001

Fuzzy Maximal Ideals Of Gamma Near-Rings, Young Bae Yun, Kyung Ho Kim, Mehmet Ali̇ Öztürk

Turkish Journal of Mathematics

Fuzzy maximal ideals and complete normal fuzzy ideals in \Gamma-near-rings are considered, and related properties are investigated.


On The Lebesgue Measure Of Self-Affine Sets, İbrahi̇m Kirat Jan 2001

On The Lebesgue Measure Of Self-Affine Sets, İbrahi̇m Kirat

Turkish Journal of Mathematics

Flaherty and Wang studied Haar-type multiwavelets and multi-tiles. The information on what digit sets give multi-attractors with positive Lebesgue measure is very limited. In this note, we give a few classes of digit sets leading to multi-attractors with positive measure. The attractors we obtain include the Haar-type multi-tiles of Flaherty and Wang.


On An Application Of The Hardy Classes To The Riemann Zeta-Function, K. Ilgar Eroglu, Iossif V. Ostrovskii Jan 2001

On An Application Of The Hardy Classes To The Riemann Zeta-Function, K. Ilgar Eroglu, Iossif V. Ostrovskii

Turkish Journal of Mathematics

We show that the function f(z) : = \frac{z}{1-z} \zeta (\frac{1}{1-z}), z < 1, belongs to the Hardy class H_{p} if and only if 0 < p < 1.


Tangent Lines Of Generalized Regular Curves Parametrized By Time Scales, Gusei̇n Gusei̇nov, Emi̇n Özyilmaz Jan 2001

Tangent Lines Of Generalized Regular Curves Parametrized By Time Scales, Gusei̇n Gusei̇nov, Emi̇n Özyilmaz

Turkish Journal of Mathematics

In this paper a generalization of the notion of regular curve is introduced. For such curves the concept of tangent line is investigated.


On The Semi-Markovian Random Walk Process With Reflecting And Delaying Barrriers, Selahatti̇n Maden Jan 2001

On The Semi-Markovian Random Walk Process With Reflecting And Delaying Barrriers, Selahatti̇n Maden

Turkish Journal of Mathematics

In this paper, a semi-Markovian random walk process X(t) with reflecting barrier on the zero-level and delaying barrier on the \beta(\beta>0 )-level and the first falling moment of the process into the delaying barrier, (\gamma), are considered. Some probability characteristics of \gamma , such as its distribution function, moment generating function and expected value are calculated.


On Qr-Submanifolds Of A Quaternionic Space Form, Bayram Şahi̇n Jan 2001

On Qr-Submanifolds Of A Quaternionic Space Form, Bayram Şahi̇n

Turkish Journal of Mathematics

In this paper, we investigate mixed QR-submanifolds in a quaternionic space form and pseudo umbilical QR-submanifold of a quaternionic space form under some additional condition. Finally we give a necessary condition for QR-submanifold of a quaternion Kaehler manifold such that \dim \upsilon ^{\perp }=1 to be a 3-quasi Sasakian Manifold.