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Full-Text Articles in Physical Sciences and Mathematics

A Note On Locally Graded Minimal Non-Metahamiltonian Groups, Sevgi̇ Atlihan Jan 2017

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.


The Role Of The Ideal Elements In Studying The Structure Of Some Ordered Semigroups, Niovi Kehayopulu Jan 2017

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 …


Depth And Stanley Depth Of The Path Ideal Associated To An $N$-Cyclic Graph, Guangjun Zhu Jan 2017

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 $n$.


Stationary Distribution And Global Asymptotic Stability Of A Three-Species Stochastic Food-Chain System, Hong Qiu, Wenmin Deng Jan 2017

Stationary Distribution And Global Asymptotic Stability Of A Three-Species Stochastic Food-Chain System, Hong Qiu, Wenmin Deng

Turkish Journal of Mathematics

This paper intends to study some dynamical properties of a stochasticthree-dimensional Lotka--Volterra system. Under some mild assumptions, we first introduce a simple method to show thatthe model has a global and positive solution almost surely. Secondly,we prove that this model has a stationary distribution. Then we study the global asymptoticstability of the positive solution. Finally, some numerical simulations are introduced toillustrate the theoretical results.


Examples Of Self-Dual Codes Over Some Sub-Hopf Algebras Of The Steenrod Algebra, Tane Vergi̇li̇, İsmet Karaca Jan 2017

Examples Of Self-Dual Codes Over Some Sub-Hopf Algebras Of The Steenrod Algebra, Tane Vergi̇li̇, İsmet Karaca

Turkish Journal of Mathematics

Codes over the finite sub-Hopf algebras $A(n)$ of the (mod 2) Steenrod algebra $\mathcal{A}$ were studied by Dougherty and Vergili. In this paper we study some Euclidean and Hermitian self-dual codes over $A(n)$ by considering Milnor basis elements.


Chaos-Related Properties On The Product Of Semiflows, Alica Miller, Chad Money Jan 2017

Chaos-Related Properties On The Product Of Semiflows, Alica Miller, Chad Money

Turkish Journal of Mathematics

In this paper we generalize some results about the chaos-related properties on the product of two semiflows, which appeared in the lite\-rature in the last few years, to the case of the most general possible acting monoids. In order to do that we introduce some new notions, namely the notions of a directional, psp and sip monoid, and the notion of a strongly transitive semiflow. In particular, we obtain a sufficient condition for the Devaney chaoticity of a product, which works for the (very large) class of the psp acting monoids.


On Subdirectly Irreducible Regular Bands, Zheng-Pan Wang, Jing Leng, Hou-Yi Yu Jan 2017

On Subdirectly Irreducible Regular Bands, Zheng-Pan Wang, Jing Leng, Hou-Yi Yu

Turkish Journal of Mathematics

Subdirectly irreducible regular bands whose structural semilattices are finite chains are characterized in terms of arefined semilattice of semigroups.


Tetravalent Normal Edge-Transitive Cayley Graphs On A Certain Group Of Order $6n$, Mohammad Reza Darafsheh, Maysam Yaghoobian Jan 2017

Tetravalent Normal Edge-Transitive Cayley Graphs On A Certain Group Of Order $6n$, Mohammad Reza Darafsheh, Maysam Yaghoobian

Turkish Journal of Mathematics

Let $U_{6n}= \langle a,b a^{2n}=b^{3}=1,a^{-1}ba=b^{-1}\rangle $ be a groupof order 6n. In this paper tetravalent normal edge-transitive Cayleygraphs on $U_{6n}$ are considered. In this way several nonequivalent normaledge-transitive Cayley graphs on $U_{6n}$ are obtained whose automorphismgroups are given exactly.


On The Rate Of $L_P$-Convergence Of Balakrishnan—Rubin-Type Hypersingular Integrals Associated To The Gauss-Weierstrass Semigroup, Meli̇h Eryi̇ği̇t, Seli̇m Çobanoğlu Jan 2017

On The Rate Of $L_P$-Convergence Of Balakrishnan—Rubin-Type Hypersingular Integrals Associated To The Gauss-Weierstrass Semigroup, Meli̇h Eryi̇ği̇t, Seli̇m Çobanoğlu

Turkish Journal of Mathematics

We introduce a family of Balakrishnan—Rubin-type hypersingular integrals depending ona parameter $\varepsilon$ and generated by the Gauss—Weierstrass semigroup. Then the connection between the order of $L_p$—smoothness of a $L_p$—function $\varphi$and the rate of $L_p$-convergence of these families to $\varphi$, as $\varepsilon$ tends to 0, is obtained.


Braided Regular Crossed Modules Bifibered Over Regular Groupoids, Alper Odabaş, Erdal Ulualan Jan 2017

Braided Regular Crossed Modules Bifibered Over Regular Groupoids, Alper Odabaş, Erdal Ulualan

Turkish Journal of Mathematics

We show that the forgetful functor from the category ofbraided regular crossed modules to the category of regular (or whiskered) groupoids is a fibration and also a cofibration.


Dissipative Operator And Its Cayley Transform, Eki̇n Uğurlu, Kenan Taş Jan 2017

Dissipative Operator And Its Cayley Transform, Eki̇n Uğurlu, Kenan Taş

Turkish Journal of Mathematics

In this paper, we investigate the spectral properties of the maximaldissipative extension of the minimal symmetric differential operatorgenerated by a second order differential expression and dissipative andeigenparameter dependent boundary conditions. For this purpose we use thecharacteristic function of the maximal dissipative operator and inverseoperator. This investigation is done by the characteristic function of theCayley transform of the maximal dissipative operator, which is a completelynonunitary contraction belonging to the class $C_{0}.$ Using Solomyak'smethod we also introduce the self-adjoint dilation of the maximal dissipativeoperator and incoming/outgoing eigenfunctions of the dilation. Moreover, weinvestigate other properties of the Cayley transform of the maximaldissipative operator.


Arf Numerical Semigroups, Sedat İlhan, Hali̇l İbrahi̇m Karakaş Jan 2017

Arf Numerical Semigroups, Sedat İlhan, Hali̇l İbrahi̇m Karakaş

Turkish Journal of Mathematics

The aim of this work is to exhibit the relationship between the Arf closure of a numerical semigroup$S$ and its Lipman semigroup $L(S).$ This relationship is then used to give direct proofs of some characterizations of Arf numerical semigroups through their Lipman sequences of semigroups. We also give an algorithmic construction of the Arf closure of a numerical semigroup via its Lipman sequence of semigroups.


A Note On The Conjugacy Problem For Finite Sylow Subgroups Of Linear Pseudofinite Groups, Pinar Uğurlu Kowalski̇ Jan 2017

A Note On The Conjugacy Problem For Finite Sylow Subgroups Of Linear Pseudofinite Groups, Pinar Uğurlu Kowalski̇

Turkish Journal of Mathematics

We prove the conjugacy of Sylow $2$-subgroups in pseudofinite $\mathfrak{M}_c$ (in particular linear) groups under the assumption that there is at least one finite Sylow $2$-subgroup. We observe the importance of the pseudofiniteness assumption by analyzing an example of a linear group with nonconjugate finite Sylow $2$-subgroups, which was constructed by Platonov.


On The Extended Spectrum Of Some Quasinormal Operators, Meltem Sertbaş, Fati̇h Yilmaz Jan 2017

On The Extended Spectrum Of Some Quasinormal Operators, Meltem Sertbaş, Fati̇h Yilmaz

Turkish Journal of Mathematics

In this paper we consider some extended eigenvalue problems for some quasinormal operators. The spectrum of an algebra homomorphism defined by a compact normal operator is also investigated.


Some Notes On $Gqn$ Rings, Long Wang, Junchao Wei Jan 2017

Some Notes On $Gqn$ Rings, Long Wang, Junchao Wei

Turkish Journal of Mathematics

A ring $R$ is called ageneralized quasinormal ring (abbreviated as $GQN$ ring) if $ea∈N(R)$ for each $e∈ E(R)$ and $a∈ N(R)$. The class of $GQN$ rings is a proper generalization of quasinormal rings and $NI$ rings. Many properties of quasinormal rings are extended to $GQN$ rings. For a$GQN$ ring $R$ and $a∈ R$, it is shown that:1) if $a$ is a regular element, then $a$ is a strongly regular element;2) if $a$ is an exchange element, then $a$ is clean;3) if $R$ is a semiperiodic ring with $J(R)\neq N(R)$, then $R$ is commutative;4) if $R$ is an $MVNR$, then $R$ …


Universal Central Extensions Of $\Mathfrak{Sl}(M, N, A)$ Over Associative Superalgebras, Xabier García-Martínez, Manuel Ladra Jan 2017

Universal Central Extensions Of $\Mathfrak{Sl}(M, N, A)$ Over Associative Superalgebras, Xabier García-Martínez, Manuel Ladra

Turkish Journal of Mathematics

We find the universal central extension of the matrix superalgebras $\mathfrak{sl}(m, n, A)$, where $A$ is an associative superalgebra and $m+n = 3, 4$, and its relation with the Steinberg superalgebra $\mathfrak{st}(m, n,A)).$ We calculate $H_2$ $(\mathfrak{sl}(m, n,A))$ and $H_2$ $(\mathfrak{st}(m, n,A))$. Finally, we introduce a new method using the nonabelian tensor product of Lie superalgebras to and the connection between $H_2$ $(\mathfrak{sl}(m, n, A))$ and the cyclic homology of associative superalgebras for $m+n \geq 3$.


Modules Satisfying Double Chain Condition On Nonfinitely Generated Submodules Have Krull Dimension, Maryam Davoudian Jan 2017

Modules Satisfying Double Chain Condition On Nonfinitely Generated Submodules Have Krull Dimension, Maryam Davoudian

Turkish Journal of Mathematics

We prove the result in the title. We study submodules $N$ of a module $M$ such that whenever $\frac{M}{N}$ satisfies the double infinite chain condition so does $M$.Moreover, we observe that an $\alpha $-atomic module, where $\alpha\geq 2$ is an ordinal number, satisfies the previous chain if and only if it satisfies the descending chain condition on nonfinitely generated submodules.


Generalization Of The Gauss--Lucas Theorem For Bicomplex Polynomials, Mahmood Bidkham, Sara Ahamadi Jan 2017

Generalization Of The Gauss--Lucas Theorem For Bicomplex Polynomials, Mahmood Bidkham, Sara Ahamadi

Turkish Journal of Mathematics

The aim of this paper is to extend the domain of the Gauss—Lucas theorem from the set of complex numbers to the set of bicomplex numbers. We also discuss a bicomplex version of another compact generalization of the Gauss—Lucas theorem.


A Bivariate Sampling Series Involving Mixed Partial Derivatives, Rashad Mudhish Asharabi, Hamoud Al-Haddad Jan 2017

A Bivariate Sampling Series Involving Mixed Partial Derivatives, Rashad Mudhish Asharabi, Hamoud Al-Haddad

Turkish Journal of Mathematics

Recently Fang and Li established a sampling formula that involves only samples from the function and its first partial derivatives for functions from Bernstein space, $B^{p}_{\sigma}(\mathbb{R}^{2})$. In this paper, we derive a general bivariate sampling series for the entire function of two variables that satisfy certain growth conditions. This general bivariate sampling formula involves samples from the function and its mixed and nonmixed partial derivatives. Some known sampling series will be special cases of our formula, like the sampling series of Parzen, Peterson and Middleton, and Gosselin. The truncated series of this formula are used to approximate functions from the …


Ranges And Kernels Of Derivations, Mohamed Ech Chad Jan 2017

Ranges And Kernels Of Derivations, Mohamed Ech Chad

Turkish Journal of Mathematics

In this paper we establish some properties concerning the class of operators $A\in {\cal L(H)}$ that satisfy $\overline{ { \cal R }(\delta_{A})}\cap\{A\}'=\{0\}$, where $\overline{ { \cal R }(\delta_{A})}$ is the norm closure of the range of the inner derivation $\delta_{A},$ defined on ${\cal L(H)}$ by $\delta_{A}(X)=AX-XA$. Here ${\cal H}$ stands for a Hilbert space; as a consequence, we show that the set $\{ A \in { \cal L(H)}\;\;/\;\;\overline{ { \cal R }(\delta_{A})}\cap\{A\}'=\{0\} \}$ is norm-dense. We also describe some classes of operators $A,\;B$ for which we have $\overline{ { \cal R }(\delta_{A,B})}\cap\ker(\delta_{A^{\ast},B^{\ast}})=\{0\}$ ($\ker(\delta_{A^{\ast},B^{\ast}})$ is the kernel of the generalized derivation …


P-Subordination Chains And P-Valence Integral Operators, Erhan Deni̇z, Hali̇t Orhan, Murat Çağlar Jan 2017

P-Subordination Chains And P-Valence Integral Operators, Erhan Deni̇z, Hali̇t Orhan, Murat Çağlar

Turkish Journal of Mathematics

In the present investigation we obtain some sufficient conditions for the analyticity and the $p$-valence of an integral operator in the unit disk $\mathbb{D}$. Using these conditions we give some applications for a few different integral operators. The significant relationships and relevance to other results are also given. A number of known univalent conditions would follow upon specializing the parameters involved in our main results.


New Inequalities Of Opial Type For Conformable Fractional Integrals, Mehmet Zeki̇ Sarikaya, Hüseyi̇n Budak Jan 2017

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.


Cyclic Codes Over $\Mathbb{Z}_{4}+U\Mathbb{Z}_{4}+U^{2}\Mathbb{Z}_{4}$, Mehmet Özen, Nazmi̇ye Tuğba Özzai̇m, Nuh Aydin Jan 2017

Cyclic Codes Over $\Mathbb{Z}_{4}+U\Mathbb{Z}_{4}+U^{2}\Mathbb{Z}_{4}$, Mehmet Özen, Nazmi̇ye Tuğba Özzai̇m, Nuh Aydin

Turkish Journal of Mathematics

In this paper, we study cyclic codes over the ring $R=\mathbb{Z}_{4}+u\mathbb{Z}_{4}+u^{2}\mathbb{Z}_{4}$,where $u^{3}=0$. We investigate Galois extensions of this ring and the ideal structure of these extensions.The results are then used to obtain facts about cyclic codes over $R$. We also determine the general form of the generator of a cyclic code and find its minimal spanning sets. Finally, we obtain many new linear codes over $\mathbb{Z}_4$ by considering Gray images of cyclic codes over $R$.


Stability Analysis Of Nonlinear Fractional Differential Order Systems With Caputo And Riemann--Liouville Derivatives, Javad Alidousti, Reza Khoshsiar Ghaziani, Ali Bayati Eshkaftaki Jan 2017

Stability Analysis Of Nonlinear Fractional Differential Order Systems With Caputo And Riemann--Liouville Derivatives, Javad Alidousti, Reza Khoshsiar Ghaziani, Ali Bayati Eshkaftaki

Turkish Journal of Mathematics

In this paper we establish stability theorems for nonlinear fractional orders systems (FDEs) with Caputo and Riemann--Liouville derivatives. In particular, we derive conditions for $ {\bf \cal{F}}$-stability of nonlinear FDEs. By numerical simulations, we verify numerically our theoretical results on a test example.


Unions And Ideals Of Locally Strongly Porous Sets, Maya Altinok, Oleksiy Dovgoshey, Mehmet Küçükaslan Jan 2017

Unions And Ideals Of Locally Strongly Porous Sets, Maya Altinok, Oleksiy Dovgoshey, Mehmet Küçükaslan

Turkish Journal of Mathematics

For subsets of $\mathbb R^+ = [0,∞)$ we introduce a notion of coherently porous sets as the sets for which the upper limit in the definition of porosity at a point is attained along the same sequence. We prove that the union of two strongly porous at $0$ sets is strongly porous if and only if these sets are coherently porous. This result leads to a characteristic property of the intersection of all maximal ideals contained in the family of strongly porous at $0$ subsets of $\mathbb R^+$. It is also shown that the union of a set $A \subseteq …


Sufficient Conditions On Nonunitary Operators That Imply The Unitary Operators, Pabitra Kumar Jena Jan 2017

Sufficient Conditions On Nonunitary Operators That Imply The Unitary Operators, Pabitra Kumar Jena

Turkish Journal of Mathematics

In this paper, we give sufficient conditions on nonunitary operators on the Bergman space that imply the unitary operators.


Approximation Of Analytic Functions Of Severalvariables By Linear K-Positive Operators, Tüli̇n Coşkun Jan 2017

Approximation Of Analytic Functions Of Severalvariables By Linear K-Positive Operators, Tüli̇n Coşkun

Turkish Journal of Mathematics

We investigate the approximation of analytic functions of several variables in polydiscs by the sequences of linear k-positive operators in the Gadjiev sense.


Factorization With Respect To A Divisor-Closed Multiplicative Submonoid Of A Ring, Ashkan Nikseresht, Abdulrasool Azizi Jan 2017

Factorization With Respect To A Divisor-Closed Multiplicative Submonoid Of A Ring, Ashkan Nikseresht, Abdulrasool Azizi

Turkish Journal of Mathematics

In this paper, we consider factorizations of elements of a divisor-closed multiplicative submonoid of a ring and also factorizations of elements of a module as a product of elements coming from a divisor-closed multiplicative submonoid of the ring and another element of the module. In particular, we study uniqueness and some other properties of such factorizations and investigate the behavior of these factorizations under direct sum and product of rings and modules.


On $\Lambda$-Perfect Maps, Mehrdad Namdari, Mohammad Ali Siavoshi Jan 2017

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 $\alpha, \beta\leq\lambda$.


Meromorphic Function And Its Difference Operator Share Two Sets With Weight K, Bingmao Deng, Dan Liu, Degui Yang Jan 2017

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.