فهرست مطالب

Caspian Journal of Mathematical Sciences
Volume:5 Issue: 1, Winter and Spring 2016

  • تاریخ انتشار: 1395/03/12
  • تعداد عناوین: 5
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  • M. H. Rahmani Doust *, A. Ghsem Abadi Pages 1-5

    Abstract. In the present paper a generalized Lotka-Volterra food chain system has been studied and also its dynamic behavior such as locally asymptotic stability has been analyzed in case of existing interspecies competition. Furthermore, it has been shown that the said system is permanent (in the sense of boundedness and uniformly persistent). Finally, it is proved that the nontrivial equilibrium point of the above system is locally asymptotically stable.

    Keywords: Lotka-Volterra model, boundedness, food chain
  • M. Bekar *, Y. Yayli Pages 7-16

    An involution or anti-involution is a self-inverse linear mapping. In this paper, we will present two real quaternion matrices, one corresponding to a real quaternion involution and one corresponding to a real quaternion anti-involution. Moreover, properties and geometrical meanings of these matrices will be given as reflections in R^3.

    Keywords: Real quaternions, Involutions, Anti-involutions
  • V. Dadashi *, M. Hosseini Pages 17-21
    In this paper, we studied maximal monotonicity of type FPV for sum of two maximal monotone operators of type FPV and the obtained results improve and complete the corresponding results of this filed.
    Keywords: Maximal monotone operator, Maximal monotone operator of type FPV, Subdifferential
  • M. Mayghani, D. Alimohammadi * Pages 23-35

    Let (X, d) be a compact metric space and let K be a nonempty compact subset of X. Let α ∈ (0, 1] and let Lip(X, K, dα ) denote the Banach algebra of all continuous complex-valued functions f on X for which p(K,dα)(f) = sup{ |f(x)−f(y)| dα(x,y) : x, y ∈ K, x 6= y} < ∞ when equipped with the algebra norm ||f||Lip(X,K,dα) = ||f||X +p(K,dα)(f), where ||f||X = sup{|f(x)| : x ∈ X}. We denote by lip(X, K, dα ) the closed subalgebra of Lip(X, K, dα ) consisting of all f ∈ Lip(X, K, dα ) for which |f(x)−f(y)| dα(x,y) → 0 as d(x, y) → 0 with x, y ∈ K. In this paper we show that every proper closed ideal of (lip(X, K, dα ), k · kLip(X,K,dα)) is the intersection of all maximal ideals containing it. We also prove that every continuous point derivation of lip(X, K, dα ) is zero. Next we show that lip(X, K, dα ) is weakly amenable if α ∈ (0, 1 2 ). We also prove that lip(T, K, d 1 2 ) is weakly amenable where T = {z ∈ C : |z| = 1}, d is the Euclidean metric on T and K is a nonempty compact set in (T, d).

    Keywords: Banach function algebra, Extended Lipschitz algebra, Point derivation, Weak amenability
  • E. Yankson * Pages 37-46

    We prove the existence of solutions for the neutral periodic integro-differential equation with infinite delay x 0 (t) = G(t, x(t), x(t − τ (t))) + d dtQ(t, x(t − τ (t))) + Z t −∞ Xn j=1 gj (t, s)  f(x(s))ds, x(t + T) = x(t). A Krasnoselskii and Banach’s fixed point theorems are employed in establishing our results.

    * The formulas are not displayed correctly.

    Keywords: Krasnoselskii's Fixed point theorem, integro-differential neutral equation, periodic solution