let r be a prime ring with extended centroid c, h a generalized derivation of r and n ⩾ 1 a xed integer. in this paper we study the situations: (1) if (h(xy))n = (h(x))n(h(y))n for all x; y 2 r; (2) obtain some related result in case r is a noncommutative banach algebra and h is continuous or spectrally bounded.

the quasi-periodic order is a type of geometrical order in universe which is observed in the structure of quasi-crystals. this order was first introduced in mathematics in 1973 by roger penrose and then discovered in quasi-crystals in 1984 while spreading in mathematics, chemistry and physics. the paper professor james lu et al published in science magazine in 2007 illustrated that iranians wer...

Neighborhoods and neighborhood sequences play important roles in several branches of pattern analysis. In earlier papers in Zn only certain special (e.g. periodic or octagonal) sequences were investigated. In this paper we study neighborhood sequences which are either ultimately periodic or allow at every neighborhood to do nothing at no cost. We give finite procedures and descriptive theoretic...

A 1-D coordination polymer, constructed using a combination of diols and phenolic oximes, contains a novel [Mn(9)] sub-unit, a nanosized [Mn(40)] octagonal super-structure and a [Mn(21)] repeating unit.

In the recent year, distributed computing systems are one of most efficient and a very popular approach of computing as compared to the old centralized computing systems. Such network processing environment provides a very high performance computing in a very low cost. Once such computing implemented in proposed topological architecture for static interconnection, achieves the desired accuracy....

In the recent year, distributed computing systems have become very popular approach of computing in comparison of old centralized computing systems due to high performance computing in a very low cost. Topological design for static interconnection of computer systems under distributed environment plays a very vital role to achieve the desired accuracy in a low cost. For the topological design, ...

Application of the quasi-uniform grids in global models of the atmosphere is an attempt to increase the computational efficiency by a more cost effective exploitation of the computing infrastructure. This paper describes the development of a global version of NCEP’s regional, step-coordinate, Eta model on two quasi-uniform girds: cubic and octagonal. The governing equations are expressed in a g...