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In this paper, by developing the Capacitated P-Median Problem (CPMP) mathematical planning model, we try to model the problem in such a way that the service to customers according to the service level is effective in the optimum solution, and to some extent, brings the CPMP closer to actual circumstances. Adding the service level will convert the CPMP from a deterministic state to a stochastic model in which demands can have any distribution function. If the customer demand follows the normal distribution function, this stochastic model can be converted to a Mixed Integer Nonlinear Programming. This obtained model is used in a real case study to develop tanks of an oil refinery so that the costs are minimized and the customer demand is met at an acceptable level. In addition, comparing the new model with the traditional CPMP Model, by solving a real case study, shows the efficiency of the proposed model. [ABSTRACT FROM AUTHOR]

This paper deals with new results on Gruss inequality by using recent fractional integral operators. In fact, based on the (k, s, h) -- Riemann-Liouville and the (k, h) --Hadamard fractional operators, we establish several integral results. For our results, some very recent results on the paper: [A Gruss type inequality for two weighted functions. J. Math. Computer Sci., 2018.] can be deduced as some special cases. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the concept of F--G--contraction mappings in F-metric spaces endowed with a graph and give some fixed point results for such contractions. Our results are generalization of some famous theorem in metric spaces to F--metric spaces endowed with a graph. Also, we give some examples that support obtained theoretical results. [ABSTRACT FROM AUTHOR]

The inverse data envelopment analysis is an inverse optimization problem, which can be used as an appropriate planning tool for management decisions. The typical DEA mainly focuses on post-operative evaluation of an organizational performance. Sometimes economic conditions such as economic prohibitions on exports or imports are imposed on a system. These prohibitions prevent decision-making units from best performance (efficiency one). In this case, if the system has the best performance (with a less than one efficiency score) then it will be considered as an efficient system. So, the efficiency frontier changes problem must be studied. So by making change in definition of the best efficiency amount of a system, it still has the best performance. In these situations, the inefficient units can select a real pattern instead of reaching an unrealistic pattern that is presented in ideal terms to achieve the best conditions (the best efficiency value is one). So a long-term management plan can be developed. The efficiency frontier change will be expressed inputs and outputs as a coefficient of efficiency. The frontier change looks at the changes in inputs and outputs to reach the new frontier. One of the purposes of the data envelopment analysis is the investigation of inputs and outputs amounts by changing the amount of efficiency. So far, many models must be solved to calculating these changes. Efficiency frontier problem can replace a simple mathematical model with these models. All of these advantages can improve calculating input and outputs changes and RTS will be unchanged and decision maker can estimate units RTS without solving any model. So a unit will be stayed MPSS by reducing inputs. In other frontier change methods some hyperplanes and extreme units had been deleting but our method transforms them on new frontier. So all extreme units and RTS can estimate easily. The efficiency frontier changes can delete some inefficient units so systems cost will be reduced. For this purpose, in this paper, the change in the efficiency frontier, its properties and its effect on the inverse data envelopment analysis is examined. [ABSTRACT FROM AUTHOR]

For any positive integer m, φ(m) finds out how many residues of m that are co-prime to m, where φ is the Euler's totient function. In this paper, we introduce the notion of totient and hyper totient numbers. We explore the potential links of totient, super totient and hyper totient numbers. Many postulates and characterizations of these numbers have been proposed with straight forward proofs. In the end, applications of these numbers in graph labeling have also been demonstrated over a family of well known graph. [ABSTRACT FROM AUTHOR]

In this paper, motivated by [F. Vetro, Filomat, 29:9 (2015), 2011-2020] we present some fixed point results for a class of nonexpansive self-mappings and multi-valued mappings in the framework of b-metric spaces. Our results generalize and improve the consequences of [ Khojasteh et al. Abstract and Applied Analysis, vol. 2014, Article ID 325840, 5 pages, 2014.] and [F. Vetro, Filomat, 29:9 (2015), 2011-2020]. Some examples are provided to illustrate our results. [ABSTRACT FROM AUTHOR]

MashhadBranch,IslamicAzadUniversityLet L be a Lie algebra crossed module and Actpi(L) be a pointwise inner Actor of L. In this paper, we introduce lower and upper central series of L and show that if Actpi (L/Zj(L) /InnAct (L/Zj(L) is the nilpotent of class k wherein Zj (L) denotes the nth term of the upper central series of L, then Actpi(L)/InnAct(LL) is the nilpotent of the maximum class j + k. Moreover, if dim )Li/(Li ∩ Zj(L))) ≤ (1,1), then Actnilpotentofclasspi(L) / InnAct(L) is the nilpotent of the maximum class i + j - 1. [ABSTRACT FROM AUTHOR]

In 1993, moneyhun showed that if L is a Lie algebra such that dim(L/Z(L)) =n, then dim(L²) ≤ 1/2n(n-1). The author and Saeedi investigated the converse of Moneyhun's result under some conditions .In this paper, We extend their results to obtain several upper bounds for the dimension of a Lie algebra L in terms of dimensions of L², Where L² is the derived subalgebra. Moreover, we give an upper bound for the dimension of the dimension of the c-nilpotent multiplier of a pair of Lie algebras. [ABSTRACT FROM AUTHOR]

In many organizations, ratio data are always available and are considered as a criterion for decision-making. In this case, evaluating decision making units (DMUs) with ratio data and finding targets can be of great importance. Therefore, in the present article, a method is proposed for finding the targets of decision making units employing ratio-based DEA (DEA-R) models and using value efficiency. Units with the most preferred solution (MPS) have a crucial role in finding the targets of decision making units. Thus, utilizing value efficiency by choosing MPS according to the management’s idea and DEA-R models presents a new target for ratio data. In this paper, two different ideas based on the Max-Min model are studied for 20 tourism companies. In the end, the targets of decision making units based on ratio data are provided. [ABSTRACT FROM AUTHOR]

In this paper we first introduce N̅qΔ − summable difference sequence spaces and prove some properties of these spaces. We then obtain the necessary and sufficient conditions for infinite matrix A to map these sequence spaces on the spaces c, c0 and l∞. Finally, the Hausdorff measure of noncompactness is then used to obtain the necessary and sufficient conditions for the compactness of the linear operators defined on these spaces. [ABSTRACT FROM AUTHOR]

Let U be a Hilbert A-module and L(U) the set of all adjointable A-linear maps on U. Let K = {Λx ∈ L(U, Vx) : x ∈ X } and L = {Γx ∈ L(U, Vx) : x ∈ X } be two continuous g-frames for U, K is said to be similar with L if there exists an invertible operator J ∈ L(U) such that Γx = ΛxJ, for all x ∈ X . In this paper, we define the concepts of closeness and nearness between two continuous g-frames. In particular, we show that K and L are near, if and only if they are similar. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the notion of dislocated Sb-metric space and describe some fixed point theorems concerning F-contraction in the setup of such spaces. We provide some examples to verify the effectiveness and applicability of our main results. [ABSTRACT FROM AUTHOR]

In this paper, we obtain a complete rewriting system for monoid presentation of generalized extended Hecke group H̅p,q, which is firstly defined in [8]. It gives an algorithm for getting normal form of elements and hence solving the word problem in this group. By using the normal form structure of elements of H̅p,q, we also calculate growth series. [ABSTRACT FROM AUTHOR]

In this paper, we study slant submanifolds of Riemannian manifolds with Golden structure. A Riemannian manifold ( ..., ..., φ ) is called a Golden Riemannian manifold if the (1, 1) tensor field φ on ... is a Golden structure, that is φ² = φ + I and the metric ... is φ − compatible. First, we get some new results for submanifolds of a Riemannian manifold with Golden structure. Later we characterize slant submanifolds of a Riemannian manifold with Golden structure and provide some non-trivial examples of slant submanifolds of Golden Riemannian manifolds. [ABSTRACT FROM AUTHOR]

Let f be a transcendental entire function defined in the open complex plane ℂ. A difference-monomial generated by f is an expression of the form F = fn(fm -1) ... (f (z+cj))..., where n, m and Vj are all non-negative integers. Now for the sake of definiteness let us take, Mi[f ] = fn(fm -1) ... (f (z+cj))..., where 1 ≤ i ≤ d. If M1 [f], M1 [f ],..., Mn [f] are such monomials in f as defined above, then ψ[f] = a1M1[f] + a2M2[f] + ... + anMn [f] where ai ≠ 0 (i = 1, 2,..., n) is called a difference-polynomial generated by f. In this paper, we compare the Valiron defect with the relative Nevan-linna defect of a particular type of differential-difference polynomial generated by a transcendental entire function with respect to integrated moduli of logarithmic derivative. Some examples are provided in order to justify the results obtained. [ABSTRACT FROM AUTHOR]

Let G be a graph with n vertices and m edges. The minimum edge dominating energy is defined as the sum of the absolute values of eigenvalues of the minimum edge dominating matrix of the graph G. In this paper, some lower and upper bounds for the minimum edge dominating energy of graph G are established. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a weak MT-cyclic Reich type contractions and obtain the existence theorems for best proximity point for self-mappings defined on the complete metric spaces. Our results improve and generalize some results in literature. Also, we give some applications of our results to solving some classes of non-linear integral and differential equations. [ABSTRACT FROM AUTHOR]

A larger class of algebraic hyperstructures satisfying the group-like axioms is the class of Hν-groups. In this paper, without any condition and in general, we define the Hν-normal subgroup and the Hν-quotient group of an Hν-group. We introduce the fundamental equivmalence relation of an Hν-quotient group and prove the first and third isomorphism theorems for Hν-groups. [ABSTRACT FROM AUTHOR]

This work is concerned with the initial boundary value problem for a nonlinear viscoelastic Petrovsky wave equation utt + Δ²u - ... g(t - τ) Δ²u(τ)dτ - Δut - Δutt + ut |ut|m-1 = u|u|p-1. Under suitable conditions on the relaxation function g, the global existence of solutions is obtained without any relation between m and p. The uniform decay of solutions is proved by adapting the perturbed energy method. For p > m and sufficient conditions on g, an unboundedness result of solutions is also obtained. [ABSTRACT FROM AUTHOR]

In this article, singular d-homology, singular extended dhomology, relative singular d-homology and relative singular extended d-homology functors are introduced and some axioms, such as dimension axiom, homotopy axiom, excision axiom and exactness axiom, of homology theory relative to these homologies are investigated and are proved to hold. [ABSTRACT FROM AUTHOR]

We investigate the existence of solution for a fractional integro-differential inclusion via the Caputo-Hadamard fractional derivation. We prove that dimension of the set of solutions for the inclusion problem is infinite dimensional under some conditions. [ABSTRACT FROM AUTHOR]

The eventual stability with respect to part of variables of a nonlinear differential equation with non-instantaneous impulses is studied using Lyapunov like functions. In these differential equations there are impulses, which start abruptly at some points and their action continue on given finite intervals. Sufficient conditions for eventual stability, uniform eventual stability and eventual asymptotic uniform stability with respect to part of variables of the zero solution are established. Examples are given to illustrate the results. [ABSTRACT FROM AUTHOR]

For a ring R and a monoid M, we introduce J-M-Armendariz rings which are a generalization of weak M-Armendariz and J-Armendariz rings, and we investigate their properties. We prove that if R/J (R) is a reduced ring and R is a J-M-Armendariz ring, then R is J-M x N - Armendariz, where N is a unique product monoid. It is also shown that a finitely generated Abelian group G is torsion free if and only if there exists a ring R such that R is J-G-Armendariz. [ABSTRACT FROM AUTHOR]

This study focuses some basic result in soft bi topological spaces with respect to soft points. the results include soft limit point, soft interior point, soft neighborhood, the relation between soft weak structures and soft weak closures. Moreover the study also addresses soft sequences uniqueness of limit in soft weak-Hausdorff spaces, the product of soft Hausdorff spaces with respect to soft points in different soft weak open set and the band between soft Hausdorff space and the diagonal. [ABSTRACT FROM AUTHOR]

Let R be a ring and M be a monoid. We introduce the notion of J-M-McCoy rings, as a generalization of J-McCoy and weak MMcCoy rings, and investigate their properties. It is proved that for u.p.-monoids M and N if R /J(R) is reversible, then R is J-M x N -McCoy. Also, it is shown that a ring R is J-M-McCoy if and only if R[[x]] is J-M-McCoy if and only if Tn(R) is J-M-McCoy, while the J-M-McCoy property is not Morita invariant. [ABSTRACT FROM AUTHOR]