Almost Contact Metric Structures Induced By $G_2$ Structures,
2017
TÜBİTAK
Almost Contact Metric Structures Induced By $G_2$ Structures, Nüli̇fer Özdemi̇r, Mehmet Solgun, Şi̇ri̇n Aktay
Turkish Journal of Mathematics
We study almost contact metric structures induced by 2-fold vector cross products on manifolds with $G_2$ structures. We get some results on possible classes of almost contact metric structures. Finally, we give examples.
On $\Lambda$-Perfect Maps,
2017
TÜBİTAK
On $\Lambda$-Perfect Maps, Mehrdad Namdari, Mohammad Ali Siavoshi
Turkish Journal of Mathematics
$\lambda$-Perfect maps, a generalization of perfect maps (i.e. continuous closed maps with compact fibers) are presented. Using $P_\lambda$-spaces and the concept of $\lambda$-compactness some classical results regarding $\lambda$-perfect maps will be extended. In particular, we show that if the composition $fg$ is a $\lambda$-perfect map where $f,g$ are continuous maps with $fg$ well-defined, then $f,g$ are $\alpha$-perfect and $\beta$-perfect, respectively, on appropriate spaces, where $\alpha, \beta\leq\lambda$.
Terminal Value Problem For Causal Differential Equations With A Caputofractional Derivative,
2017
TÜBİTAK
Terminal Value Problem For Causal Differential Equations With A Caputofractional Derivative, Coşkun Yakar, Mehmet Arslan
Turkish Journal of Mathematics
In this paper, we have given new definitions and obtained the unique solution of a fractional causal terminal value problem by combining the technique of generalized quasilinearization in the sense of upper and lower solutions.
Some Theorems For A New Type Of Multivalued Contractivemaps On Metric Space,
2017
TÜBİTAK
Some Theorems For A New Type Of Multivalued Contractivemaps On Metric Space, Gonca Durmaz
Turkish Journal of Mathematics
In this paper, taking into account the function $\theta $, we introduce a new type of contraction for multivalued maps on metric space. This new concept includes many known contractions in the literature. We then present some fixed point results for closed and bounded set valued maps on complete metric space. Finally, we provide an example to show the significance of the investigation of this paper.
Permutation Groups With Cyclic-Block Property And $Mnfc$-Groups,
2017
TÜBİTAK
Permutation Groups With Cyclic-Block Property And $Mnfc$-Groups, Ali̇ Osman Asar
Turkish Journal of Mathematics
This work continues the investigation of perfect locally finite minimal non-$FC$-groups in totally imprimitive permutation $p$-groups. At present, the class of totally imprimitive permutation $p$-groups satisfying the cyclic-block property is known to be the only class of $p$-groups having common properties with a hypothetical minimal non-$FC$-group, because a totally imprimitive permutation $p$-group satisfying the cyclic-block property cannot be generated by a subset of finite exponent and every non-$FC$-subgroup of it is transitive, which are the properties satisfied by a minimal non-$FC$-group. Here a sufficient condition is given for the nonexistence of minimal non-$FC$-groups in this class of permutation groups. In …
Positive Periodic Solutions To Impulsive Delay Differentialequations,
2017
TÜBİTAK
Positive Periodic Solutions To Impulsive Delay Differentialequations, Naima Daoudi-Merzagui, Fatima Dib
Turkish Journal of Mathematics
In this paper we discuss the existence of positive periodic solutions for nonautonomous second order delay differential equations with singular nonlinearities in the presence of impulsive effects. Simple sufficient conditions are provided that enable us to obtain positive periodic solutions. Our approach is based on a variational method.
Unicorn Metrics With Almost Vanishing ${\Bf H}$- And ${\Bf \Xi}$-Curvatures,
2017
TÜBİTAK
Unicorn Metrics With Almost Vanishing ${\Bf H}$- And ${\Bf \Xi}$-Curvatures, Akbar Tayebi, Tayebeh Tabatabaeifar
Turkish Journal of Mathematics
In this paper, we consider a class of almost regular $(\alpha, \beta)$-metrics constructed by Shen called unicorn metrics. First, we prove that every unicorn metric with almost vanishing ${\bf H}$-curvature is a Berwald metric. Then we show that every unicorn metric with almost vanishing $\Xi$-curvature reduces to a Berwald metric.
On The 3-Dimensional Hopf Bifurcation Via Averaging Theory Of Third Order,
2017
TÜBİTAK
On The 3-Dimensional Hopf Bifurcation Via Averaging Theory Of Third Order, Elouahma Bendib, Sabrina Badi, Ammar Makhlouf
Turkish Journal of Mathematics
We apply the averaging theory of third order to polynomial quadratic vector fields in $\mathbb{R}^3$ to study the Hopf bifurcation occurring in that polynomial. Our main result shows that at most $10$ limit cycles can bifurcate from a singular point having eigenvalues of the form $\pm bi$ and $0$. We provide an example of a quadratic polynomial differential system for which exactly $10$ limit cycles bifurcate from a such singular point.
Subspace Condition For Bernstein's Lethargy Theorem,
2017
TÜBİTAK
Subspace Condition For Bernstein's Lethargy Theorem, Asuman Güven Aksoy, Monairah Al-Ansari, Caleb Case, Qidi Peng
Turkish Journal of Mathematics
In this paper, we consider a condition on subspaces in order to improve bounds given in Bernstein's lethargy theorem for Banach spaces. Let $d_1 \geq d_2 \geq \dots d_n \geq \dots > 0$ be an infinite sequence of numbers converging to $0$, and let $Y_1 \subset Y_2 \subset \dots\subset Y_n \subset \dots \subset X$ be a sequence of closed nested subspaces in a Banach space $X$ with the property that $\overline{Y}_{n}\subset Y_{n+1}$ for all $n\ge1$. We prove that for any $c ın (0,1]$ there exists an element $x_c ın X$ such that$$ c d_n \leq \rho(x_c, Y_n) \leq \min (4, \tilde{a}) …
Schanuel's Lemma, The Snake Lemma, And Product And Direct Sum In $H_V$-Modules,
2017
TÜBİTAK
Schanuel's Lemma, The Snake Lemma, And Product And Direct Sum In $H_V$-Modules, Yaser Vaziri, Mansour Ghadiri
Turkish Journal of Mathematics
In this paper we find a generalization of the snake lemma and Schanuel's lemma in $H_v$-modules. We define the isomorph sequences and determine the conditions to split the exact sequences in $H_v$-modules. Some interesting results on these concepts are given.
The Ptolemaean Inequality In The Closure Of Complex Hyperbolic Planes,
2017
TÜBİTAK
The Ptolemaean Inequality In The Closure Of Complex Hyperbolic Planes, Ioannis D. Platis, Ni̇lgün Sönmez
Turkish Journal of Mathematics
We prove the Ptolemaean inequality andPtolemaeus' theorem in the closure of complex hyperbolic planes endowed with theCygan metric.
Some Results On Uniform Statistical Cluster Points,
2017
TÜBİTAK
Some Results On Uniform Statistical Cluster Points, Tuğba Yurdakadi̇m, Leila Miller-Van Wieren
Turkish Journal of Mathematics
In this paper, we present some results linking the uniform statistical limit superior and inferior, almost convergence and uniform statistical convergence of a sequence.We also study the relationship between the set of uniform statistical cluster points of a given sequence and its subsequences. The resultsconcerning uniform statistical convergence and uniform statistical cluster points presented here are also closelyrelated to earlier results regarding statistical convergence and statistical cluster points of a sequence.
New Inequalities Of Opial Type For Conformable Fractional Integrals,
2017
TÜBİTAK
New Inequalities Of Opial Type For Conformable Fractional Integrals, Mehmet Zeki̇ Sarikaya, Hüseyi̇n Budak
Turkish Journal of Mathematics
In this paper, some Opial-type inequalities for conformable fractionalintegrals are obtained using the remainder function of Taylor's theorem forconformable integrals.
Meromorphic Function And Its Difference Operator Share Two Sets With Weight K,
2017
TÜBİTAK
Meromorphic Function And Its Difference Operator Share Two Sets With Weight K, Bingmao Deng, Dan Liu, Degui Yang
Turkish Journal of Mathematics
In this paper, we utilize Nevanlinna value distribution theory to study the uniqueness problem that a meromorphic function and its difference operator share two sets with weight $k$. Our results extend the previous results.
The Role Of The Ideal Elements In Studying The Structure Of Some Ordered Semigroups,
2017
TÜBİTAK
The Role Of The Ideal Elements In Studying The Structure Of Some Ordered Semigroups, Niovi Kehayopulu
Turkish Journal of Mathematics
The aim of writing this paper is given in the title. We want to show that not only the ideals but also the ideal elements play an essential role in studying the structure of some ordered semigroups.We first prove that a $\vee e$-semigroup $S$ is a semilattice of left simple $\vee e$-semigroups if and only if it is decomposable into some pairwise disjoint left simple $\vee e$-subsemigroups of $S$ indexed by a semilattice $Y$. Then we give an example of a semilattice of left simple $\vee e$-semigroups that leads to a characterization of the semilattices of left simple and the …
Character Analogue Of The Boole Summation Formula With Applications,
2017
TÜBİTAK
Character Analogue Of The Boole Summation Formula With Applications, Mümün Can, Muhammet Ci̇hat Dağli
Turkish Journal of Mathematics
In this paper, we present the character analogue of the Boole summationformula. Using this formula, an integral representation is derived for thealternating Dirichlet $L$-function and its derivative is evaluated at $s=0$.Some applications of the character analogue of the Boole summation formula andthe integral representation are given about the alternating Dirichlet $L$-function. Moreover, the reciprocity formulas for two new arithmetic sums,arising from the summation formulas, and for Hardy--Berndt sum $S_{p}(b,c:\chi)$ are proved.
Depth And Stanley Depth Of The Path Ideal Associated To An $N$-Cyclic Graph,
2017
TÜBİTAK
Depth And Stanley Depth Of The Path Ideal Associated To An $N$-Cyclic Graph, Guangjun Zhu
Turkish Journal of Mathematics
We compute the depth and Stanley depth for the quotient ringof the path ideal of length $3$ associated to a $n$-cyclic graph, given some precise formulas for the depth when $n\not\equiv 1\,(\mbox{mod}\ 4)$, tight bounds when $n\equiv 1\,(\mbox{mod}\ 4)$,and for Stanley depth when $n\equiv 0,3\,(\mbox{mod}\ 4)$, tight bounds when $n\equiv 1,2\,(\mbox{mod}\ 4)$. We also give some formulas forthe depth and Stanley depth of a quotient of the path ideals of length $n-1$ and $n$.
A Note On Locally Graded Minimal Non-Metahamiltonian Groups,
2017
TÜBİTAK
A Note On Locally Graded Minimal Non-Metahamiltonian Groups, Sevgi̇ Atlihan
Turkish Journal of Mathematics
We prove that a nonperfect locally gradedminimal non-metahamiltonian group $G$ is a soluble group withderived length of at most 4. On the other hand, if $G$ is perfect,then $G/\Phi (G)$ is isomorphic to $A_{5}$, where $\Phi (G)$ isthe Frattini subgroup of $G$ and $A_{5}$ is the alternating group.Moreover, we show that under some conditions,if G is a $p$-group, then G is metabelian, where $p$ is a prime integer.
Some Properties Of Alternate Duals And Approximate Alternate Duals Of Fusion Frames,
2017
TÜBİTAK
Some Properties Of Alternate Duals And Approximate Alternate Duals Of Fusion Frames, Ali Akbar Arefijamaal, Fahimeh Arabyani Neyshaburi
Turkish Journal of Mathematics
In this paper we extend the notion of approximate dual to fusion frames and present some approaches to obtain alternate dual and approximate alternate dual fusion frames. We also study the stability of alternate dual and approximate alternate dual fusion frames.
A New Approach To Uniqueness For Inverse Sturm-Liouville Problems On Finite Intervals,
2017
TÜBİTAK
A New Approach To Uniqueness For Inverse Sturm-Liouville Problems On Finite Intervals, Seyfollah Mosazadeh
Turkish Journal of Mathematics
In this paper, an approach for studying inverse Sturm--Liouville problems with integrable potentials on finite intervals is presented. We find the relations between Weyl solutions and $m_{j}$-functions of Sturm--Liouville problems, and by finding the connection between these and the solutions of second-order partial differential equations for transformation kernels associated with Sturm--Liouville operators, we prove the uniqueness of the solution of inverse problems.
