Let A be an algebra and let X be an A-bimodule. A C−linear mapping d : A → X is called a generalized Jordan derivation if there exists a Jordan derivation (in the usual sense) δ : A → X such that d(a) = ad(a) + δ(a)a for all a ∈ A. The main purpose of this paper to prove the Hyers-Ulam-Rassias stability and superstability of the generalized Jordan derivations.

In a great many cases the methods used in the proofs of the above theorems can be used to determine whether a given continuum is a Wn set. In particular, they can be used to prove that no W-¡ set, M, has a complementary domain whose boundary, /, contains three limit points of B(M) — J, no Wi set has a complementary domain whose boundary contains five such points, and that there exists a Wo set ...

We prove in this paper that there exists some infinitary rational relations which are Σ03-complete Borel sets and some others which are Π03-complete. These results give additional answers to questions of Simonnet [Sim92] and of Lescow and Thomas [Tho90] [LT94].

We define a pair of simple combinatorial operations on subshifts, called existential and universal extensions, and study their basic properties. We prove that the existential extension of a sofic shift by another sofic shift is always sofic, and the same holds for the universal extension in one dimension. However, we also show by a construction that universal extensions of twodimensional sofic ...

We present the Cards corpus of task-oriented dialogues and show how it can inform study of the ways in which discourse is goaland preference-driven. We report on three experimental studies involving underspecified referential expressions and quantifier domain restriction.

We define II(n) to be the largest number such that for every set P of n points in the plane, there exist two points x, y e P, where every circle containing x and y contains H(n) points of P. We establish lower and upper bounds for H(n) and show that [n/27J + 2 ~ H ( n ) < [ n / 4 ] + l . We define I~I(n) for the special case where the n points are restricted to be the vertices of a convex polyg...

We investigate the uniqueness of stable coalition structures, when the value of a coalition to a member depends solely on the identity of the other members of the coalition. We give a complete characterization of collections of coalitions which ensure that there is a unique stable coalition structure at every preference profile when only admissible coalitions may form. An alternative characteri...

In this survey paper, we present several results linking quantifier-free axiomatizations of various Euclidean and hyperbolic geometries in languages without relation symbols to geometric constructibility theorems. Several fragments of Euclidean and hyperbolic geometries turn out to be naturally occurring only when we ask for the universal theory of the standard plane (Euclidean or hyperbolic), ...

This paper reports the syntactic distribution of amwu-N-to/-irato/-ina phrases, which are representative polarity sensitive items (PSIs) in Korean, and accounts for their semantic characteristics in terms of "arbitrary choice quantification" and "concession." In the first section, we extensively illustrate the distributional behaviour of the PSIs in various constructions and roughly generalizes...