فهرست مطالب

  • Volume:14 Issue:1, 2019
  • تاریخ انتشار: 1398/01/12
  • تعداد عناوین: 15
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  • R. Arulprakasam*, V. R. Dare, S. Gnanasekara Pages 1-11

    In formal language theory, we are mainly interested in the natural language computational aspects of ω-languages. Therefore in this respect it is convenient to consider fuzzy ω-languages. In this paper, we introduce two subclasses of fuzzy regular ω-languages called fuzzy n-local ω-languages and Buchi fuzzy n-local ω-languages, and give some closure properties for those subclasses. We define a deterministic fuzzy automaton acceptance conditions on fuzzy ω-languages and fuzzy n-local automaton. The relationship between deterministic fuzzy n-local automaton and two subclasses of fuzzy regular ω-languages are established and proved that every fuzzy ω-language accepted by a deterministic fuzzy automaton in 2-mode is a projection of a Buchi fuzzy 2-local ω-language.

    Keywords: Fuzzy set, Local ω-language, Deterministic fuzzy automaton, Fuzzy regular ω-languages.
  • T. Narang, S. Gupta* Pages 13-20

    As a counterpart to best approximation, a new kind of approximation, called best coapproximation was introduced in normed linear spaces by C. Franchetti and M. Furi. In this paper, we use this coapproximation to prove some results on the existence and uniqueness of best coapproximation in quotient spaces when the underlying spaces are metric linear spaces. We shall also see how coproximinality can be transmitted to and from quotient spaces.

    Keywords: Best coapproximation, co-proximinal set, co-Chebyshev set, Boundedly compact set, Pseudo co-Chebyshev set.
  • F. Bardestani*, S. R. Adhami Pages 21-34

    In network code setting, a constant dimension code is a set of k-dimensional subspaces of F nq . If F_q n is a nondegenerated symlectic vector space with bilinear form f, an isotropic subspace U of F n q is a subspace that for all x, y ∈ U, f(x, y) = 0. We introduce isotropic subspace codes simply as a set of isotropic subspaces and show how the isotropic property use in decoding process, then we show that for suitable parameters there are isotropic spread codes.

    Keywords: Isotropic subspace, Constant dimension subspace code, Spread Codes.
  • F. Ramezani*, E. Vatandoost Pages 35-42

    In this paper, we investigate domination number as well as signed domination numbers of Cay(G : S) for all cyclic group G of order n, where n in {p^m; pq} and S = { a^i : i in B(1; n)}. We also introduce some families of connected regular graphs gamma such that gamma_S(Gamma) in {2,3,4,5 }.

    Keywords: Cayley graph, cyclic group, Domination number, Signed domination number.
  • A. Molabahrami* Pages 43-53

    In this paper, the system of Fredholm integral equations of the second kind is investigated by using a modified degenerate kernel  method (MDKM). To construct a MDKM the source function is approximated by the same way of producing degenerate kernel. The interpolation is used to make the needed approximations. Lagrange polynomials are adopted for the interpolation. The equivalency of  proposed method and  Lagrange-collocation method is shown. The error and convergence of the algorithm are given strictly. The efficiency of the approach will be shown by applying the procedure on some prototype examples.

    Keywords: A system of Fredholm integral equations of the second kind, Degenerate kernel method, A modified degenerate kernel method, Lagrange interpolation method, Lagrange-collocation method.
  • A. Rezaei Aliabad, M. Parsinia* Pages 55-67

    Let X be a topological space and R be a subring of RX. By determining some special topologies on X associated with the subring R, characterizations of maximal fixxed and maximal growing ideals in R of the form Mx(R) are given. Moreover, the classes of zR-ideals and z0R-ideals are introduced in R which are topological generalizations of z-ideals and z0-ideals of C(X), respectively. Various characterizations of these ideals are established, also, coincidence of zR-ideals with z-ideals and zR-ideals with z-ideals in R are investigated. It turns out that some fundamental statements in the context of C(X) are extended to the subrings of RX

    Keywords: Z(R)-topology, Coz(R)-topology, Growing ideal, z, R- ideal, z^0, R-ideal, Invertible subring.
  • R. Mahjoob*, T. Vougioklis Pages 69-79

    The largest class of hyperstructures is the one which satisfies the  weak properties. We connect the theory of P-hopes, a large class of  hyperoperations, with the Lie-Santilli admissibility used in  Hardonic Mechanics. This can be achieved by a kind of Ree,  sandwich hyperoperation.

    Keywords: H, v-structures, Hopes.
  • E. Rostami*, R. Nekooei Pages 81-93

    In this paper, we consider the minimum Hamming weight for linear codes over special finite quasi-Frobenius rings. Furthermore, we obtain minimal free $R$-submodules of a finite quasi-Frobenius ring $R$  which contain a linear code and derive the relation between their minimum Hamming weights. Finally, we suggest an algorithm that computes this weight using the Grobner basis and we show that under certain conditions a linear code takes the maximum of minimum Hamming weight.

    Keywords: Algebraic coding theory, Linear codes, Quasi-Frobenius rings, Grobner basis, SPAP-rings
  • M. El Moumni* Pages 95-119

    The purpose of this paper is to prove the existence of a renormalized solution of perturbed elliptic problems$ -operatorname{div}Big(a(x,u,nabla u)+Phi(u) Big)+ g(x,u,nabla u) = mumbox{ in }Omega,  $ in the framework of Orlicz-Sobolev spaces without any restriction on the $M$ N-function of the Orlicz spaces, where $-operatorname{div}Big(a(x,u,nabla u)Big)$ is a Leray-Lions operator defined from $W^{1}_{0}L_{M}(Omega)$ into its dual, $Phi in C^{0}(mathbb{R},mathbb{R}^{N})$. The function $g(x,u,nabla u)$ is a non linear lower  order term with natural growth with respect to $|nabla u|$, satisfying the sign condition and the  datum $mu$ is assumed belong to $L^1(Omega)+W^{-1}E_{overline{M}}(Omega)$.

    Keywords: Elliptic equation, Orlicz-Sobolev spaces, Renormalized solution.
  • M. Ramezani*, H. Baghani Pages 121-126

    In this paper, first, we introduce the new concept of 2-inner product on Banach modules over a $C^*$-algebra. Next,  we present the concept of 2-linear operators over a $C^*$-algebra. Our result improve  the main result of the paper  Z. Lewandowska.  In the final of this paper, we define the notions 2-adjointable mappings between 2-pre Hilbert C*-modules and prove supperstability of them in the spirit of Hyers-Ulam-Rassias.

    Keywords: $C^*$-algebra, 2-Adjointable mapping, Supperstability.
  • A. Tehranian*, R. Moghimipor Pages 127-134

    Let L be the generalized mixed product ideal induced by a monomial ideal I. In this paper we compute powers of the genearlized mixed product ideals and show that Lk  have a linear resolution if and only if Ik have a linear resolution for all k. We also introduce the generalized mixed polymatroidal ideals and prove that powers and monomial localizations of a generalized mixed polymatroidal ideal is again generalized mixed polymatroidal ideal.

    Keywords: Free resolutoins, Graded betti numbers, Monomial ideals
  • H. Mousavi, R. Mohammadi, S. Rahimi* Pages 135-145

    In this paper, we classify the skew cyclic codes over Fp + vF_p + v^2F_p, where p is a prime number and v^3 = v. Each skew cyclic code is a F_p+vF_p+v^2F_p-submodule of the (F_p+vF_p+v^2F_p)[x;alpha], where v^3 = v and alpha(v) = -v. Also, we give an explicit forms for the generator of these codes. Moreover, an algorithm of encoding and decoding for these codes is presented.

    Keywords: Skew Cycilc Codes, Skew Polynomial Rings, Hamming Distance.
  • S. Babaei, Sh. Payrovi*, E. Sengelen Sevim Pages 147-157

    ‎Let $R$ be commutative ring with identity and $M$ be an $R$-module‎. ‎The zero divisor graph of $M$ is denoted $Gamma{(M)}$‎. ‎In this study‎, ‎we are going to generalize the zero divisor graph $Gamma(M)$ to submodule-based zero divisor graph $Gamma(M‎, ‎N)$ by replacing elements whose product is zero with elements whose product is in some submodules $N$ of $M$‎. ‎The main objective of this paper is to study the interplay of the properties of submodule $N$ and‎ ‎the properties of $Gamma(M‎, ‎N)$‎.

    Keywords: Zero-divisor graph‎, ‎Submodule-based zero-divisor graph‎, ‎ Semi simple module.
  • Sh. Modak*, T. Noiri Pages 159-165

    Arenas et al. [1] introduced the notion of lambda-closed sets as a generalization of locally closed sets. In this paper, we introduce the notions of lambda-locally closed sets, Lambda_lambda-closed sets and lambda_g-closed sets and obtain some decompositions of closed sets and continuity in topological spaces.

    Keywords: lambda-open set, lambda-locally closed set, Lambda, lambda-closed set, lambda, g-closed set, decompositions of continuity.
  • H. Fukhar, Ud, Din* Pages 167-179

    We construct one-step iterative process for an α- nonexpansive mapping and a mapping satisfying condition (C) in the framework of a convex metric space. We study △-convergence and strong convergence of the iterative process to the common fixed point of the mappings. Our results are new and are valid in hyperbolic spaces, CAT(0) spaces, Banach spaces and Hilbert spaces, simultaneously.

    Keywords: Convex metric space, α-Nonexpansive mapping, Condition(C), Common fixed point, One-step iterative process, Convergence