Search

This paper is concerned with the existence of solutions for initial value problems of functional and neutral functional Hadamard type fractional differential inclusions. We apply appropriate fixed point theorems for multivalued maps to obtain the existence results for the given problems covering convex as well as non-convex cases. Some illustrative examples are also presented. [ABSTRACT FROM AUTHOR]

Let R be a semiprime ring with center Z(R). A mapping F: R→ R is called a generalized derivation if there exists a derivation d : R→R such that F(xy) = F(x)y+xd(y) holds for all x,yϵR. In the present paper, our main object is to study the situations: (1) F(xy)-F(x)F (y)ϵ Z(R), (2) F(xy)+F(x)F(y)ϵ Z(R), (3) F(xy)-F(y)F(x) ϵ Z(R), (4) F(xy)+F(y)F(x) ϵ Z(R); for all x,y in some suitable subset of R. [ABSTRACT FROM AUTHOR]

One of the outstanding problems in combinatorial design theory is concerning the existence of 2-(v,k, 1) designs. In particular, the existence of 2-(v,k, 1) designs admitting an interesting group of automorphisms is of great interest. Thirty years ago, a six-person team classified 2-(v,k, 1) designs which have flag-transitive automorphism groups. Since then the effort has been to classify those 2-(v,k, 1) designs which are block-transitive but not flagtransitive. This paper is a contribution to this program and we prove there is nonexistence of 2-(v,k, 1) designs admitting a point-primitive block-transitive but not flag-transitive automorphism group G with socle Eg(q). [ABSTRACT FROM AUTHOR]

In this paper we propose a new collocation type method for solving Volterra integral equations of the second kind with weakly singular kernels. In this method we use the complex Bspline basics in collocation method for solving Volterra integral. We compare the results obtained by this method with exact solution. A few numerical examples are presented to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, our approach allows to refine the results announced by Ebadian et al. [Results Math., 36 (2013), 409-423]. Namely, we reduce the distance between approximate and exact double derivations on Banach algebras and Lie C*-algebras up to 1/2n-1 and 1/2n-2 for n⩾2. Indeed, we give a correct utilization of fixed point theory in the sense of Diaz and Margolis [Bull. Amer. Math. Soc., 74 (1968), 305-309] concerning the stability of double derivations. [ABSTRACT FROM AUTHOR]

In this paper, the existence of solution for generalized equilibrium problems under compactness or non-compactness assumptions in abstract convex spaces is proved. The closedness and the convexity of the solution set are also obtained. Our results generalize and improve some recent results in the literature. [ABSTRACT FROM AUTHOR]

This paper is devoted to finding explicit formulas for two kinds of reproducing kernels in some reproducing kernel spaces. Usually for calculating the reproducing kernel of space Wm2 [a;b], one must solve a large system of ordinary differential equations with 4m equations in 4m unknowns. Hence, it is worthy to have explicit formulas to save time and computational efforts. The advantage of using these formulas is clearly seen in the plotted graphs. [ABSTRACT FROM AUTHOR]

The object of the present paper is to prove the existence of a generalized quasi Einstein spacetime, briefly G(QE)4, by constructing a non-trivial Lorentzian metric and to study such spacetime. First, we prove that every W2-Ricci pseudosymmetric G(QE)4 is an N(k)-quasi Einstein spacetime which can be considered as a model of perfect fluid, in general relativity. Then, we consider Ricci symmetric G(QE)4 and we prove that in such spacetime satisfying Einstein's field equations, the energy density and the isotropic pressure are constants. As a consequence of this result, the expansion scalar and the acceleration vector vanish and also the possible local cosmological structures of this spacetime obeying Einstein's field equations are of Petrov I, D or O. [ABSTRACT FROM AUTHOR]

In this paper two modifications of Kolchin's generalized allocation scheme are studied. Results known for Kolchin's scheme are extended to the new models. Representation theorems, strong laws of large numbers and local limit theorems are obtained. In the proofs some general inequalities are used. [ABSTRACT FROM AUTHOR]

The paper introduces some sets of double lacunary invariant sequences defined by four dimensional RH-regular matrices and Orlicz functions. First we study some basic properties of such sets by equipping them with linear topological structure. Further, we investigate some relationships among such sets under different conditions and finally compare with a set of double lacunary statistically convergent sequences. [ABSTRACT FROM AUTHOR]

The first geometric-arithmetic index GA1(G), which was introduced by D. Vukiċević and B. Furtula recently, is a graph-based molecular structure descriptor. The aim of this paper is to obtain new inequalities involving the geometric-arithmetic index GA1 and other well known topological indices. In particular, we relate the geometric-arithmetic index of a graph G with its first Zagreb index M1(G), its second Zagreb index M2(G), its modified Zagreb index Z-1(G) and its Randić index R(G). [ABSTRACT FROM AUTHOR]

In this paper, we have given a criteria for the existence of common fixed point for pair of mappings in 2-metric spaces and establish common fixed point theorems for certain class of contractive type mappings. The results presented here, generalize some well known fixed point theorems given in the literature. [ABSTRACT FROM AUTHOR]

The functional defined as the difference of the right-hand and the left-hand side of Jensen's inequality is called Jensen's functional. The aim of this paper is to study its lower bounds. More precisely, some refinements of its lower bounds are recaptured under more relaxed conditions on the n-tuple x. [ABSTRACT FROM AUTHOR]

In this paper we establish some Tauberian-like conditions in terms of the weighted general control modulo of integer order to retrieve subsequential convergence of a sequence from its boundedness. [ABSTRACT FROM AUTHOR]

In this paper, the consimilarity of complex matrices is generalized for commutative quaternion matrices. In this regard, the coneigenvalue and coneigenvector for commutative quaternion matrices are defined. Also, the existence of solution to the some commutative quaternion matrix equations is characterized and solutions of these matrix equations are derived by means of real representations of commutative quaternion matrices. [ABSTRACT FROM AUTHOR]

In this paper, we will show Tauberian conditions under which λstatistical convergence follows from (V,λ)-statistical convergence. Our results generalize the ones given in [3]. [ABSTRACT FROM AUTHOR]

Let R be a prime ring of characteristic not 2, U a nonzero square closed Lie ideal of R and F;G;H be the generalized derivations with associated derivations d,δh of R respectively. In the present paper, we study the situations if one the follwoing holds (1) F(u)G(v)±H(uv)ϵ Z(R), (2) F(u)F (v)±H(vu) ϵ Z(R), for all u,v ϵ U, then U ⊆Z(R). [ABSTRACT FROM AUTHOR]

In this paper, we obtained some fixed point results for continuous mappings satisfying a generalized contractive condition in the setting of two metrics space endowed with a binary relation. Our theorems generalize and extend several known results in the literature. As application, we establish an existence theorem for the solution of a nonlinear first order differential equation. [ABSTRACT FROM AUTHOR]

In this paper, we study Baskakov type positive operators in polynomial weighted spaces of functions of two variables. We obtain some well known operators by using our operators which are special cases of them. We give theorems on approximation, on the degrees of approximations of functions and the Vornovskaya type theorem for these operators. Finally, we present an open problem concerning the q analogue of these operators. [ABSTRACT FROM AUTHOR]

Let λD(λn) be a non-decreasing sequence of positive real numbers tending to1with λn+1 ⩽λn+1;λ1 D1: In the present paper, we introduce the notion of Ʌ-statistical convergence of order, α, Ʌ-statistical Cauchy sequences of order α in random 2-normed spaces and obtain some results. We display examples which show that our method of convergence is more general in random 2-normed space. [ABSTRACT FROM AUTHOR]

Let 0< ρ

In this paper, we prove some Tauberian remainder theorems for Cesàro summability method of noninteger order >α-1. [ABSTRACT FROM AUTHOR]

Let W = {w1;w2; … ;wk} be an ordered set of vertices of G and let v be a vertex of G. The representation r(v|W) of v with respect to W is the k-tuple (d(v,w1),d(v,w2), … ; d(v,wk)). W is called a resolving set or a locating set if every vertex of G is uniquely identified by its distances from the vertices of W, or equivalently, if distinct vertices of G have distinct representations with respect to W . A resolving set of minimum cardinality is called a metric basis for G and this cardinality is the metric dimension of G, denoted by dim(G). Metric dimension is a generalization of affine dimension to arbitrary metric spaces (provided a resolving set exists). In this paper, we study the metric dimension of barycentric subdivision of Cayley graphs Cay(Zn ⊕Zm). We prove that these subdivisions of Cayley graphs have constant metric dimension and only three vertices chosen appropriately suffice to resolve all the vertices of Cayley graphs Cay(Zn⊕Zm). [ABSTRACT FROM AUTHOR]

In this paper, we introduce the multivariate Bernstein-Schurer-Stancu operators. Then, we state the Volkov-type theorem and investigate the order of convergence by means of modulus of continuity and by Lipschitz class functionals. Moreover, the inverse theorems are studied for the multivariate Stancu variant of Bernstein operators. [ABSTRACT FROM AUTHOR]

Zeros of minimizers of p-Ginzburg-Landau functional are helpful to understand the location of vortices of superconductivity and superfluid. When p D 2 and the degree of the boundary data around the boundary is ±1, there exists only one zero of the p-Ginzburg-Landau minimizers in the bounded domain. When p > 2, this becomes a more complicated problem. This paper is concerned with the location of the zeros of a radial minimizer of a p-Ginzburg-Landau type functional. The authors use the method of moving planes and the idea of the proof of Pohozaev's identity to verify that the origin is the unique zero of the radial minimizer in the domain. [ABSTRACT FROM AUTHOR]

In this paper, we introduce ρ-generalized pseudo and ρ-genera-lized quasi with the tool right upper-Dini-derivative and illustrated these by non-trivial examples. Necessary and sufficient optimality conditions are obtained for a nonlinear multiobjective fractional programming problem involving some classes of generalized convexities with the tool-right upper-Dini-derivative. Furthermore, usual duality theorems are proved for a general dual problem using the concept of generalized convex functions. Our results generalize and extend the several results appeared in the literature. [ABSTRACT FROM AUTHOR]

In this paper, a model of two teams of predators interacting with two teams of preys is proposed. The predator teams help each other and so do the prey teams. Therefore, some stability analysis are carried out on the model to detect the stability and instability of the system's equilibrium solutions. Also, the persistence of the solutions is investigated. Finally, the optimal control is applied to the unstable equilibrium solutions. Some numerical simulations are carried out to verify the analytic results. [ABSTRACT FROM AUTHOR]

In this paper we recover convergence and subsequential convergence of a sequence of real numbers regularly generated by another sequence in some sequence spaces under certain conditions. We also give some information about the behavior of a sequence whose generator is given in terms of a moderately divergent sequence. [ABSTRACT FROM AUTHOR]

Let C.(R) denote the center of a ring R and g.(x) be a polynomial of ring C.R(x). An element r ϵ R is called "g(x)-clean" if r = s+u where g(s) = 0 and u is a unit of R and R is g(x)-clean if every element is g(x)-clean. In this paper, we introduce the concept of g(x)-full clean rings and study various properties of them. [ABSTRACT FROM AUTHOR]

A selection of ring theory papers by Jenő Szigeti is reviewed with an emphasis on aspects related to matrix algebras. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of linear systems of neutral differential equations with delay. Assuming the linear parts to be given by pairwise permutable matrices, representation of a solution of a nonhomogeneous initial value problem using matrix polynomial of a degree depending on time is derived. Examples illustrating the obtained results are given. [ABSTRACT FROM AUTHOR]

In the present paper, two new subclasses of bi-starlike and bi-convex function of complex order associated with hypergeometric functions are introduced and coefficient estimates for functions in these classes are obtained. Several new (or known) consequences of the results are also pointed out. [ABSTRACT FROM AUTHOR]

Let I be a nonzero ideal of a ring T , let φ : T → E:= T/I denote the canonical projection, let D be a ring contained in E, and let R = φ-1(D). The main purpose of this paper is to characterize when the ring extension R ⊂ T is n- (resp., universally) algebraic modulo I in case I is an intersection of finitely many maximal ideals of T. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to prove the following result: Let R be a prime ring with involution of the second kind and with char(R) ≠ 2. If R admits a nonzero derivation d : R → R such that [d(x),d(x*)]= [x,x*] for all x ∊ R, then R is commutative. We also provide an example which shows that the above result does not holds in case the involution is of the first kind. Moreover, a related result has also been obtained. [ABSTRACT FROM AUTHOR]

In this paper, by the weighted ergodic function based on the measure theory, we study the pseudo asymptotic behavior of mild solution for semilinear fractional integro-differential equations. The existence, unique of μ-pseudo anti-periodic (μ-pseudo periodic, μ-pseudo almost periodic, μ-pseudo almost automorphic) solution are investigated. Moreover, an application to fractional partial differential equations is given. [ABSTRACT FROM AUTHOR]

The goal of this paper is to introduce new q-Stancu-Kantorovich operators and to study some of their approximation properties. A convergence theorem using the well known Bohman- Korovkin criterion is proven and the rate of convergence involving the modulus of continuity is established. Furthermore, a Voronovskaja type theorem is also proven. [ABSTRACT FROM AUTHOR]

In this paper, some new integral inequalities of Hermite-Hadamard type are presented for functions whose nth derivatives in absolute value are s-logarithmically convex. From our results, several inequalities of Hermite-Hadamard type can be derived in terms of functions whose first and second derivatives in absolute value are s-logarithmically convex functions as special cases. Our results may provide refinements of some results for s-logarithmically convex functions already exist in literature. Finally, applications to special means of the established results are given. [ABSTRACT FROM AUTHOR]

In this paper, a one-sided condition is given to recover (C,α) summability of a sequence from its (A)(C, α+1) summability. Our result extends and generalizes the well known classical Tauberian theorems given for Abel and Cesàro summability methods. [ABSTRACT FROM AUTHOR]

In this paper we consider a problem for the first order Dirac differential equations system with spectral parameter dependent on boundary condition. The asymptotic behaviors of eigenvalues, eigenfunctions and normalizing numbers of this system are investigated. The expansion formula with respect to eigenfunctions is obtained and Parseval equality is given. The main theorem on necessary and sufficient conditions for the solvability of inverse problem is proved and the algorithm of reconstruction of potential from spectral data (the sets of eigenvalues and normalizing numbers) is given. [ABSTRACT FROM AUTHOR]

In this paper, a known theorem dealing with an application of quasi power increasing sequences has extended by using a new class of increasing sequences instead of a quasi-σ-power increasing sequence. This theorem also includes some new and known results. [ABSTRACT FROM AUTHOR]

In this paper, we prove some fixed point results using mixed weakly monotone property and altering distance function in the setting of S-metric space. Our result generalizes the result of Lakshmikantham and Ciric [V. Lakshmikantham and L. Ciric, Coupled common fixed point theorems for nonlinear contractions in partially ordered metric spaces, Nonlinear Analysis, 70, (2009), 4341 - 4349]. [ABSTRACT FROM AUTHOR]

In this paper we show that on complete metric spaces the class of weakly Picard operators contains some operators which are more general than the class of almost contractions. [ABSTRACT FROM AUTHOR]

In the present paper we investigate commutativity of *-prime ring R, which satisfies certain differential identities on *-ideals of R. Some results already known for prime rings on ideals have also been deduced. Finally, we provide several examples to justify that various restrictions imposed in the hypotheses of our theorems are not superfluous. [ABSTRACT FROM AUTHOR]

The harmonic index of a graph G is defined as the sum of the weights 2/d(u)+d(u) of all edges uv of G, where d(u) denotes the degree of a vertex u in G. In this paper, we present the minimum harmonic indices for unicyclic and bicyclic graphs with n vertices and matching number m (2 ≤ m ≤ [n/2]), respectively. The corresponding extremal graphs are also characterized. [ABSTRACT FROM AUTHOR]

The paper is concerned with the semisimplicity of smash products of generalized quantum commutative algebras in weak Hopf algebra setting. Let H be a weak Hopf algebra over a field k and A any semisimple and generalized quantum commutative weak Yetter-Drinfeld H-module algebra. It is shown that A♯H is semisimple if and only if A is a projective left A♯Hmodule. Applying results to quasitriangular (weak) Hopf algebras is considered. [ABSTRACT FROM AUTHOR]

In this paper we investigate the generalized Hyers-Ulam stability of mappings of m-semigroups m ∊ N; m ≥ 2 into Banach spaces. For m = 3 the results can be found in Amyari and Moslehian [Approximate homomorphisms of ternary semigroups, Lett. Math. Phys. 77 (2006), 1-9] with the mention that they are true in the class of normal m-semigroups which is larger than the class of commutative m-semigroups. For m = 2 we find certain results of Hyers [On the stability of the linear functional equation, Proc. Nat. Acad. Sci. USA, 27 (1941), 222-224], Aoki [On the stability of the linear transformation in Banach spaces,J. Math. Soc. Japan, 2 (1950), 64-66], Rassias, Th. M. [On the stability of the linear mapping in Banach space, Proc. Amer. Math, Soc. 72 (1978), 297-300 ] and Rassias, J. M. [Solution of a Problem of Ulam, J. Approx. Theory Math. 57 (1989), 268-273]. In addition, we establish the superstability of m-ary homomorphims into Banach algebras endowed with multiplicative norms, generalizing the results of Szekelyhidi [On a theorem of Baker, Lawrence and Zorzitto, Proc. Amer. Math. Soc., 84 (1982), 95-96] and Amyari and Moslehian (2006). [ABSTRACT FROM AUTHOR]

This paper is devoted to studying the growth and oscillation of solutions and their derivatives of equations of the type f''+ A(z) f' + B(z) f = F(z), where A(z), B(z) (≢0) and F(z) (≢0) are meromorphic functions of finite order. [ABSTRACT FROM AUTHOR]

In this paper we prove the continuity for the multilinear commutator associated to the Marcinkiewicz operator on Besov spaces. [ABSTRACT FROM AUTHOR]

In this paper we consider the following nonlocal boundary value problems (p(t)x')'=f(t,x,x'), x'(0)=∣0, x(1)=∫10 x'(s)dg(s) and (p(t)x')'=f(t,x,x'), x'(0)=0, x(1)=∫10 x(s)dg(s), where f:[0,1]×Rk×Rk → Rk and the integrals are meant in the sense of Riemann-Stieltjes. Under a sign condition on the function f , we prove the existence of solutions [ABSTRACT FROM AUTHOR]

In the present paper we introduce some new sequence spaces in the n-normed space. We define here some new spaces of double sequences by using the notions of lacunary sequences, difference sequences, almost convergence, sequence of Orlicz functions and statistical convergence. We examine some topological properties of these spaces of double sequences, inclusion relations between these newly defined sequence spaces and establish relation with lacunary statistical convergence. The study of these new sequence spaces provides a tool to deal with convergence problems of double sequences. [ABSTRACT FROM AUTHOR]