Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Oscillation (27)
- Fixed point (25)
- Convex function (21)
- Fixed point theorem (21)
- Stability (20)
-
- Analytic functions (19)
- Time scales (18)
- Analytic function (16)
- Bi-univalent functions (16)
- Derivation (16)
- Univalent functions (16)
- Eigenvalues (14)
- Subordination (14)
- Boundary value problem (13)
- Eigenvalue (13)
- Asymptotic behavior (12)
- Collocation method (11)
- Crossed modules (11)
- Existence (11)
- Ideal (11)
- Rank (11)
- Coefficient bounds (10)
- Fractional derivative (10)
- Green's function (10)
- Numerical semigroup (10)
- Positive solution (10)
- Positive solutions (10)
- Riemannian manifold (10)
- Riemannian submersion (10)
- Spectrum (10)
- Publication Year
Articles 1 - 30 of 2781
Full-Text Articles in Entire DC Network
Generalized Spectral Bound For Quasi-Twisted Codes, Buket Özkaya
Generalized Spectral Bound For Quasi-Twisted Codes, Buket Özkaya
Turkish Journal of Mathematics
Minimum distance bounds play a central role in the analysis of algebraic codes. For cyclic and constacyclic codes, several bounds based on their zero set have been developed. However, analogous results for quasi-twisted (QT) codes are comparatively limited. In this paper, we further investigate the spectral theory of QT codes and derive a general spectral bound on their minimum distance. Our bound unifies and generalizes previously known spectral bounds for quasi-cyclic (QC) and QT codes, and contains them as special cases. We present a new proof technique and show that the bound can be formulated with respect to an arbitrary …
A Novel Iterative Algorithm For Approximating Common Fixed Points Of Generalized Α-Nonexpansive Multivalued Mappings In Kohlenbach Hyperbolic Spaces, Makbule Kaplan Özekes
A Novel Iterative Algorithm For Approximating Common Fixed Points Of Generalized Α-Nonexpansive Multivalued Mappings In Kohlenbach Hyperbolic Spaces, Makbule Kaplan Özekes
Turkish Journal of Mathematics
In this paper, we propose a new iterative scheme involving three multivalued mappings in Kohlenbach hyperbolic spaces. Strong and ∆-convergence theorems are established for approximating common fixed points of nonexpansive multivalued mappings under suitable conditions. A numerical example is also presented to illustrate the efficiency and faster convergence of the proposed method. The results obtained extend and unify several related contributions in the existing literature.
On Families Of Finsler Metrics, İsmai̇l Sağlam, Ken'ichi Ohshika, Athanase Papadopoulos
On Families Of Finsler Metrics, İsmai̇l Sağlam, Ken'ichi Ohshika, Athanase Papadopoulos
Turkish Journal of Mathematics
In this paper, we answer some natural questions concerning symmetrisation and more general combinations of Finsler metrics, with a view to applications to Funk and Hilbert geometries and metrics on Teichmüller spaces. The metrics on Teichmüller space that we consider are the Thurston metric and the earthquake metric, both introduced by Thurston. The first metric has been thoroughly studied over the last couple of decades, and the second over the last few years. The Funk metric and its symmetrisation, the Hilbert metric, are classical metrics that have been investigated in the contexts of hyperbolic geometry and geometric function theory and, …
On The Monoid Of Partial Order-Preserving Transformations Of A Finite Chain Whose Domains And Ranges Are Intervals, Hayrullah Ayik, Vítor H. Fernandes, Emrah H. Korkmaz
On The Monoid Of Partial Order-Preserving Transformations Of A Finite Chain Whose Domains And Ranges Are Intervals, Hayrullah Ayik, Vítor H. Fernandes, Emrah H. Korkmaz
Turkish Journal of Mathematics
In this paper, we consider the monoid PIOn of all partial order-preserving transformations on a chain with n elements whose domains and ranges are intervals, along with its submonoid PIOn− of order-decreasing transformations. Our main aim is to give presentations for PIOn− and PIOn. Moreover, for both monoids, we describe regular elements and determine their ranks, cardinalities and the numbers of idempotents and nilpotents.
On The Generalized Cesàro Sequence Spaces And Some Of Their Properties, Uğur Gönüllü, Faruk Polat, Martin Richard Weber
On The Generalized Cesàro Sequence Spaces And Some Of Their Properties, Uğur Gönüllü, Faruk Polat, Martin Richard Weber
Turkish Journal of Mathematics
Let Ct = (cnm)n,m∈ℕ denote the generalized Cesàro matrix defined by cnm = tn−m/n for m ≤ n and t ∈ [0, 1], and cnm = 0 otherwise. For each q ∈ [1, ∞), the associated generalized Cesàro sequence spaces cesqt are introduced. These spaces form Banach lattices under the coordinatewise order, equipped with a naturally defined order continuous norm. We prove that cesqt = cesq0 for all t ∈ [0, 1) and q ∈ [1, ∞), implying that the space …
A Note On The Periodic Orbits Of Wolbachia Spread Dynamics In Mosquito Populations In Periodic Environments, Jose S. Cánovas
A Note On The Periodic Orbits Of Wolbachia Spread Dynamics In Mosquito Populations In Periodic Environments, Jose S. Cánovas
Turkish Journal of Mathematics
We consider the periodic model introduced by B. Zheng and J. Yu, and disprove the conjectures on the number of periodic orbits the model can have. We rebuild the conjecture to prove that for periodic sequences of maps of any period, the number of nonzero periodic trajectories is bounded by two.
Characterizations Of Bi-Riordan Arrays, Nai̇m Tuğlu, Fatma Yeşi̇l Baran
Characterizations Of Bi-Riordan Arrays, Nai̇m Tuğlu, Fatma Yeşi̇l Baran
Turkish Journal of Mathematics
In this study, we introduce the concept of a bi-Riordan array. As part of this construction, we define new composition and power operations. We then establish an analogue of the well-known fundamental theorem of Riordan arrays (FTRA), which we call the fundamental theorem of bi-Riordan arrays. Next, we show that the product of two bi-Riordan matrices is again a bi-Riordan matrix. Using this product structure, we prove that the set of bi-Riordan matrices forms a monoid.
Exponential Stability For A Strongly Damped Wave Equation With Distributed Internal Delay, Manal Alotaibi, Nasser-Eddine Tatar, Waled Al-Khulaif
Exponential Stability For A Strongly Damped Wave Equation With Distributed Internal Delay, Manal Alotaibi, Nasser-Eddine Tatar, Waled Al-Khulaif
Turkish Journal of Mathematics
This paper investigates the exponential stability of a strongly damped wave equation subject to an internal distributed time delay. Two distinct analytical frameworks are developed: the first employs a modified energy method based on auxiliary functionals, while the second introduces a transformation that rewrites the delay term as the derivative of a convolution integral. Both approaches yield explicit decay conditions and establish exponential convergence of the energy under weaker assumptions on the damping coefficient and the delay kernel. Notably, the transformation method allows for a wider class of admissible delay weights than those permitted by classical techniques. Numerical simulations based …
Clairaut Conformal Submersions From Ricci Solitons, Murat Polat
Clairaut Conformal Submersions From Ricci Solitons, Murat Polat
Turkish Journal of Mathematics
In this study, we investigate Clairaut conformal submersions in the context of total manifolds that support a Ricci soliton structure. We begin by deriving the scalar curvature and Ricci tensor expressions associated with these manifolds, and we establish criteria under which the fibres can be characterized as almost Ricci solitons or Einstein manifolds. Additionally, we identify the conditions required for the base manifold to admit Ricci soliton and Einstein structures. We also determine the necessary conditions for a vector field ζ to be conformal or Killing. Moreover, we demonstrate that when the potential vector field of the Ricci soliton is …
A Delayed Siamr Prostate Cancer Model With Vertical Transmission And Treatment: Stability Analysis And Numerical Simulation, Hüseyi̇n Demir, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keles
A Delayed Siamr Prostate Cancer Model With Vertical Transmission And Treatment: Stability Analysis And Numerical Simulation, Hüseyi̇n Demir, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keles
Turkish Journal of Mathematics
In this paper, we propose and analyse a delayed-compartmental mathematical model of prostate cancer dynamics that incorporates vertical transmission and therapeutic intervention. The population is stratified into five compartments: susceptible (S), infected/virally activated (I), asymptomatic infectious under treatment (A), malignant untreated (M), and recovered (R). A discrete time delay τ > 0 is introduced in the force-of-infection term to model the age-dependent onset of susceptibility in middle-aged adult males. Vertical transmission of viral etiology at a rate qΛ ensures that a fraction of newborns enter the infected compartment directly, rendering the disease persistent regardless of the basic reproduction number R₀. We …
Compact And Am-Compact Orthogonally Additive Operators, Bahri̇ Turan, Bi̇rol Altin
Compact And Am-Compact Orthogonally Additive Operators, Bahri̇ Turan, Bi̇rol Altin
Turkish Journal of Mathematics
We show that compactness of orthogonally additive operators between Banach lattices is not preserved under taking the modulus by providing a nonlinear analogue of Krengel’s example. In contrast, for operators acting from a Banach lattice into an AM-space, AM-compactness is stable under lattice operations. Moreover, the space of absolutely norm bounded AM-compactorthogonally additive operators from a Banach lattice into an AM-space is a Banach lattice, and on such AM-spaces with the weak Fatou property, norm boundedness coincides with absolute norm boundedness.
Hyers-Ulam And Hyers-Ulam Rassias Stability Of Caputo Fractional Hahn Difference Equations, Karima Mohamed Oraby, Alaa E. Hamza, Afrah Al-Bossly
Hyers-Ulam And Hyers-Ulam Rassias Stability Of Caputo Fractional Hahn Difference Equations, Karima Mohamed Oraby, Alaa E. Hamza, Afrah Al-Bossly
Turkish Journal of Mathematics
In this paper, we investigate Hyers–Ulam and Hyers–Ulam–Rassias stability for fractional linear Hahn difference equations of Caputo Type. To the best of our knowledge, this is the first work concerning Hyers–Ulam type stability in the framework of Caputo fractional Hahn difference equations, thereby filling a significant gap in the literature on fractional stability theory. Our approach is based on establishing an equivalence between the fractional Hahn difference initial value problem and a corresponding fractional integral equation, via the Caputo–Hahn inversion formula. These results lay a strong groundwork for analyzing the stability of Hahn fractional systems, which could be useful in …
Stochastic Control Of Inventory And Scheduling Decisions In An Open Network Of Repairables, Erhun Özkan
Stochastic Control Of Inventory And Scheduling Decisions In An Open Network Of Repairables, Erhun Özkan
Turkish Journal of Mathematics
We study maintenance operations for capital goods with repairable components. Because the downtime of a capital good is costly, the maintenance provider keeps an inventory of spare parts to quickly replace broken parts of the capital goods. After the replacement, the broken part is added to the repair facility’s repair queue. Upon a part breakdown, if there is no spare part in the inventory, then the maintenance provider has two options: (i) it can backorder the spare part demand, (ii) it can execute an emergency repair, which is done immediately and quickly, and is followed by a quick installation of …
A Full-Scale Watertight Workflow Numerical Study For A Triangular Fin And Tube Heat Exchanger, Hamdi̇ Selçuk Çeli̇k, Bahadir Doğan, Lati̇fe Berri̇n Erbay
A Full-Scale Watertight Workflow Numerical Study For A Triangular Fin And Tube Heat Exchanger, Hamdi̇ Selçuk Çeli̇k, Bahadir Doğan, Lati̇fe Berri̇n Erbay
Turkish Journal of Mathematics
In this study, the thermo-hydraulic characteristics of an air-cooled triangular finned tube heat exchanger were analyzed numerically. The full-scale heat exchanger was modeled using Ansys Fluent watertight workflow, considering water as the primer fluid to precisely investigate the effects of geometrical factors. The effects of fin height, fin width, and fin spacing of the triangular fins on the performance of the heat exchanger were examined using k-ω turbulence model. A basic finned-tube heat exchanger model, which was manufactured as a monolithic structure without tube-fin contact resistance by milling from aluminum 5083 material, was tested in an air tunnel to verify …
Generalized Splines Over ℤ-Modules On Arbitrary Graphs, Gökçen Di̇laver, Selma Altinok
Generalized Splines Over ℤ-Modules On Arbitrary Graphs, Gökçen Di̇laver, Selma Altinok
Turkish Journal of Mathematics
Let [[EQUATION]] be a commutative ring with identity and [[EQUATION]] a graph. Fix an [[EQUATION]]-module [[EQUATION]] for each vertex [[EQUATION]] of [[EQUATION]], an extending generalized spline on [[EQUATION]] is a vertex labeling [[EQUATION]], where for each edge [[EQUATION]] there exists an [[EQUATION]]-module [[EQUATION]] together with homomorphisms [[EQUATION]] and [[EQUATION]] such that [[EQUATION]]. Extending generalized splines are further generalizations for generalized splines. They can also be considered as generalized splines over modules.In this paper, we prove that some of the results for splines can be extended to extending generalized splines when [[EQUATION]] for each vertex [[EQUATION]], and we define a method …
On Construction Of Mannheim Curves With Myller Configuration, Zehra İşbi̇li̇r, Bahar Doğan Yazici, Murat Tosun
On Construction Of Mannheim Curves With Myller Configuration, Zehra İşbi̇li̇r, Bahar Doğan Yazici, Murat Tosun
Turkish Journal of Mathematics
In this study, our aim is to strengthen the results of the existing literature on the concept of Mannheim curves by using the natural and idiosyncratic structure of Myller configuration. For this purpose, we examine Mannheim curves with Frenet-type frame in Myller configuration for Euclidean 3-space E3 and Euclidean 4-space E4. Since the classical Frenet frames in E3 and E4 are special cases of Frenet-type frames with Myller configuration in E3 and E4, and because of the special and natural structure of the Myller configuration, the Mannheim curves with Frenet frames in …
Biquandle Virtual Brackets And Virtual Knotoids, Nesli̇han Gügümcü, Hamdi̇ Kayaslan
Biquandle Virtual Brackets And Virtual Knotoids, Nesli̇han Gügümcü, Hamdi̇ Kayaslan
Turkish Journal of Mathematics
In this paper, we introduce invariants of virtual knotoids based on biquandles and biquandle virtual brackets. We show that one of these invariants, namely biquandle virtual bracket matrix, is a proper enhancement of the other invariants introduced in this paper.
Disjoint Supercyclic Pseudo-Shifts, Nurhan Çolakoğlu
Disjoint Supercyclic Pseudo-Shifts, Nurhan Çolakoğlu
Turkish Journal of Mathematics
We give a characterization for disjoint supercyclicity of a finite number of unilateral pseudo-shift operators on [[EQUATION]]. We also characterize unilateral pseudo-shifts that satisfy the Disjoint Supercyclicity Criterion.
A New Characterization Of Globally Conformal Kenmotsu Manifolds And Lagrangian Submersions, Beran Pi̇ri̇nççi̇, Çağrihan Çi̇men, Deni̇z Ulusoy, Hakan Mete Taştan
A New Characterization Of Globally Conformal Kenmotsu Manifolds And Lagrangian Submersions, Beran Pi̇ri̇nççi̇, Çağrihan Çi̇men, Deni̇z Ulusoy, Hakan Mete Taştan
Turkish Journal of Mathematics
We give a characterization theorem for a globally conformal Kenmotsu manifold with an illustrative example. Then we study Riemannian, antiinvariant and Lagrangian submersions from globally conformal Kenmotsu manifolds. Initially, we show that the gradient vector field of the conformal transformation and the Lee vector field of the total manifold of a Riemannian submersion is horizontal when the characteristic vector field is a horizontal vector field. We give necessary and sufficient conditions for the integrability and totally geodesicness of vertical and horizontal distributions of antiinvariant and Lagrangian submersions whose total manifolds are globally conformal Kenmotsu. We also give a necessary and …
Biharmonic Curves In Warped Product Manifolds I ×FMN(C), Şaban Güvenç, Ci̇han Özgür
Biharmonic Curves In Warped Product Manifolds I ×FMN(C), Şaban Güvenç, Ci̇han Özgür
Turkish Journal of Mathematics
We explore the geometric properties of biharmonic curves in warped product manifolds of the form I ×f Mn(c), where I is an open interval and Mn(c) is a space of constant curvature. By establishing a main theorem, we analyze four distinct cases to reveal deeper curvature-related characteristics of these curves, including situations where they are slant. Finally, we construct three examples in I ×f S2(1).
Generalized Submaximality And Paracompactness In Ideal Topological Spaces Via Δβ*-𝔍-Open Sets, Chawalit Boonpok, Areeyuth Sama-Ae
Generalized Submaximality And Paracompactness In Ideal Topological Spaces Via Δβ*-𝔍-Open Sets, Chawalit Boonpok, Areeyuth Sama-Ae
Turkish Journal of Mathematics
This paper explores the notions of δβ*-𝔍-submaximality and δβ*-𝔍-paracompactness within ideal topological spaces, viewing them as natural generalizations of the traditional concepts of submaximality and paracompactness. These concepts arise naturally in the context of ideal topology, where an ideal 𝔍 on a topological space provides additional structure for analyzing topological properties. It focuses on the study of submaximal spaces by employing δβ*-𝔍-open sets, which serve as fundamental building blocks for understanding the topological behavior in ideal spaces. Furthermore, the work provides multiple characterizations of δβ*-𝔍-paracompact spaces and examines how this property behaves …
Impulsive Hahn--Sturm--Liouville Equations, Bi̇lender Paşaoğlu Allahverdiev, Hüseyi̇n Tuna, Hati̇ce Bulut Demi̇ralay
Impulsive Hahn--Sturm--Liouville Equations, Bi̇lender Paşaoğlu Allahverdiev, Hüseyi̇n Tuna, Hati̇ce Bulut Demi̇ralay
Turkish Journal of Mathematics
In this study, we investigate the Hahn--Sturm--Liouville problems with impulsive boundary conditions. The basic spectral properties of this type of equations are investigated.
The Kinematic Relationship Between Plücker Coordinates, Moments Of Ruled Surfaces, And Real Quaternion Algebra, Selahatti̇n Aslan
The Kinematic Relationship Between Plücker Coordinates, Moments Of Ruled Surfaces, And Real Quaternion Algebra, Selahatti̇n Aslan
Turkish Journal of Mathematics
This paper introduces a new kinematic method for generating ruled surfaces in Euclidean 3-space. We demonstrate that the Plücker coordinate method for straight lines can be extended to ruled surfaces. We prove that the moment of a ruled surface is a unique curve, which is independent of the chosen base curve. Moreover, we introduce a novel and distinctive base curve that is defined as the set of points on the rulings of the ruled surface such that these points are closest to the origin. Thus, we prove that each ruled surface can be generated using a real quaternion and a …
Pgl Orbits On Products Of Flag Varieties, Izzet Coşkun, Abuzer Gündüz
Pgl Orbits On Products Of Flag Varieties, Izzet Coşkun, Abuzer Gündüz
Turkish Journal of Mathematics
In this paper, we study the existence of a dense orbit for the diagonal [[EQUATION]] action on self-products of partial flag varieties. We determine when there exists a dense orbit for flag varieties of the form [[EQUATION]] when [[EQUATION]] or when [[EQUATION]] and [[EQUATION]] for some [[EQUATION]]. We also show that certain infinite families of products do not have a dense orbit.
On Statistical Multiplicative Uniform Convergence, Abdullah Aydin, Recep Türk, İrem Güler
On Statistical Multiplicative Uniform Convergence, Abdullah Aydin, Recep Türk, İrem Güler
Turkish Journal of Mathematics
This paper introduces a new concept of convergence, called statistical multiplicative uniform convergence, on Riesz algebras. This concept unifies three fundamental convergence types: statistical convergence, multiplicative convergence, and relatively uniform convergence. After establishing basic properties such as uniqueness, linearity, and compatibility with algebraic and lattice operations, we investigate its relationships with order convergence, statistical multiplicative order convergence, and relatively uniform convergence. In particular, we prove that statistical multiplica tive uniform convergence coincides with statistical multiplicative order convergence when an order unit exists. Moreover, for monotone sequences in Archimedean semiprime f-algebras, statistical multiplicative uniform convergence implies order convergence. We also study …
Notes On The Geometry Of Electromagnetic Fields And Maxwell’S Equations Along A Nonnull Curves In Nonflat-3d Space Forms MQ3(C), Fatma Almaz, Cumali̇ Eki̇ci̇
Notes On The Geometry Of Electromagnetic Fields And Maxwell’S Equations Along A Nonnull Curves In Nonflat-3d Space Forms MQ3(C), Fatma Almaz, Cumali̇ Eki̇ci̇
Turkish Journal of Mathematics
In this paper, the directional derivatives in accordance with the orthonormal frame {T→, N→, B→} are defined in Mq3(c), the extended Serret-Frenet relations by using Frenet formulas are expressed. Furthermore, we express the bending elastic energy function for the same particle in Mq3(c) according to curve γ(s, ξ, η) and we tried to interpret it from a geometric perspective of the energy for unit vector fields. Also, Maxwell’s equations are expressed for the electric and magnetic field vectors …
Analysis And Categorization Of Second-Order Linear Partial Dynamic Equations On Time Scales, Svetlin G. Georgiev, Jervin Zen Lobo, Sanket Tikare
Analysis And Categorization Of Second-Order Linear Partial Dynamic Equations On Time Scales, Svetlin G. Georgiev, Jervin Zen Lobo, Sanket Tikare
Turkish Journal of Mathematics
In this paper, we obtain the canonical form of second-order linear partial dynamic equations in two independent variables on time scales, together with the identity for the characteristic quadratic form. This is then used to classify these equations as hyperbolic, elliptic, or parabolic. We deduce the characteristic equations in each case, determine their roots, and provide the corresponding characteristic curves. In one case, we derive the generalized Beltrami equations on time scales. Suitable examples involving equations of interest are explored, and the developed theory is illustrated through these examples.
Del Pezzo Surfaces Of Degree One And Examples Of Zariski Multiples, Ichiro Shimada
Del Pezzo Surfaces Of Degree One And Examples Of Zariski Multiples, Ichiro Shimada
Turkish Journal of Mathematics
We construct examples of Zariski N-tuples with large N using the monodromy action of the Weyl group of type E8 on the set of 240 lines in a del Pezzo surface of degree one.