Journal of Applied Mathematics
Volume 2012 (2012), Article ID 185357, 18 pages
Research Article

Homomorphisms of Approximation Spaces

School of Mathematical Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, China

Received 21 December 2011; Accepted 26 February 2012

Academic Editor: George Jaiani

Copyright © 2012 Zhaohao Wang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The notion of the homomorphism of approximation spaces is introduced. Some properties of homomorphism are investigated, and some characterizations of homomorphism are given. Furthermore, the notion of approximation subspace of approximation spaces is introduced. The relations between approximation subspaces and homomorphisms are studied.