Results 51 to 60 of about 166 (76)

Random homomorphisms and random derivations in random normed algebras via fixed point method

, 2012
Using the fixed point method, we prove the Hyers-Ulam stability of the Cauchy additive functional inequality and of the Cauchy-Jensen additive functional inequality in random normed spaces.MSC:47H10, 39B52, 37H10, 60H25, 17B40, 39B72, 47B47, 54E70.
Choonkill Park, M. Eshaghi Gordji, R. Saadati   +2 more
semanticscholar   +1 more source

Poisson C*-algebra derivations in Poisson C*-algebras

Demonstratio Mathematica
In this study, we introduce the following additive functional equation:g(λu+v+2y)=λg(u)+g(v)+2g(y)g\left(\lambda u+v+2y)=\lambda g\left(u)+g\left(v)+2g(y) for all λ∈C\lambda \in {\mathbb{C}}, all unitary elements u,vu,v in a unital Poisson C*{C ...
Wang Yongqiao, Park Choonkil, Chang Yuan
doaj   +1 more source

Approximate *-derivations and approximate quadratic *-derivations on C*-algebras

, 2011
In this paper, we prove the stability of *-derivations and of quadratic *-derivations on Banach *-algebras. We moreover prove the superstability of *-derivations and of quadratic *-derivations on C*-algebras.2000 Mathematics Subject Classification: 39B52;
S. Jang, Choonkill Park
semanticscholar   +1 more source

Functional equations in paranormed spaces

, 2012
In this paper, we prove the Hyers-Ulam stability of various functional equations in paranormed spaces.MSC:35A17, 39B52, 39B72.
Choonkill Park, D. Shin
semanticscholar   +1 more source

Stability of an AQCQ-functional equation in paranormed spaces

, 2012
Using the fixed point method and direct method, we prove the Hyers-Ulam stability of an additive-quadratic-cubic-quartic functional equation in paranormed spaces.MSC:35A17, 39B52, 47H10, 39B72.
Choonkill Park
semanticscholar   +1 more source

Functional inclusions on square-symmetric grupoids and Hyers-Ulam stability

, 2004
In this paper we prove that a set-valued map F : X → P0(Y) that satisfies the inclusion F(x ∗ y) ⊂ F(x) ♦ F(y) under suitable conditions admits exactly one selection f : X → Y that satisfies the equation f (x ∗ y) = f (x) f (y) , where (X, ∗) and (Y ...
D. Popa
semanticscholar   +1 more source

On approximately convex functions

, 1993
The Bernstein-Doetsch theorem on midconvex functions is extended to approximately midconvex functions and to approximately Wright convex functions. Let X be a real vector space, D be a convex subset of X, and c be a nonnegative constant. A function f: D -
C. T. Ng, K. Nikodem
semanticscholar   +1 more source

On Hyers-Ulam-Rassias stability of a quadratic functional equation

, 2003
In this paper, we investigate the Hyers-Ulam-Rassias stability of a new quadratic functional equation f (x + y + z + w) + 2f (x) + 2f (y) + 2f (z) + 2f (w) = f (x + y) + f (y + z) + f (z + x) + f (x + w) + f (y + w) + f (z + w).
I. Chang, Eun Hwi Lee, Hark-Mahn Kim
semanticscholar   +1 more source

On the super-stability of trigonometric Hilbert-valued functional equations

, 2014
We generalize the super-stability result for cosine functional equation mappings with values in the field of complex numbers to the case of an arbitrary Hilbert space with the Hadamard product.
H. Rezaei
semanticscholar   +1 more source

The mean ergodic theorem for nonexpansive mappings in multi-Banach spaces

, 2014
In this paper, we prove a mean ergodic theorem for nonexpansive mappings in multi-Banach spaces.MSC:39A10, 39B72, 47H10, 46B03.
H. M. Kenari, R. Saadati, Y. Cho
semanticscholar   +1 more source