عبدالله بردونی شاعر معاصر و نابینای یمنی، در سال 1929 م. در روستای بردون از توابع صنعا در خانواده‌ای تهیدست به دنیا آمد. وی در چهار سالگی بر اثر بیماری آبله بینایی خود را از دست داد و تمام عمر خویش را نابینا زیست. او در ...

We prove the stability of subquadratic functional inclusion

F(x + y) + F(x − y) ⊆ 2F(x) + 2F(y)

in the space of non-empty compact convex subsets of a topological vector space.

We use the fixed point alternative theorem to prove the stability of the set-valued functional equations.

We discuss on the generalized Ulam-Hyers stability for set-valued functional equations, including the nonlinear ...

We will show that if $F$ is a set-valued mapping which satisfies $$ F(x) + F(y) \\\\\\\\\\\\\\\\subseteq 2F\\\\\\\\\\\\\\\\Big(\\\\\\\\\\\\\\\\frac{x+y}2\\\\\\\\\\\\\\\\Big)+ K $$ for some convex compact set $K$, then ...

We investigate the stability of orthogonally additive set-valued functional equation

F({x+y}) = F(x) + F(y) (x _|_ y)

in Hausdorff topology on closed convex subsets of a Banach space.