Author/Authors :
Ameri، R نويسنده School of Mathematics, Statistics and Computer Science, College of Sciences, University of Tehran, P.O. Box 14155-6455, Teheran, Iran Ameri, R , Azizpour Arabi، S نويسنده Department of Mathematics, University of Mazandaran, Babolsar, Iran Azizpour Arabi, S , Hedayati، H نويسنده Department of Mathematics, Babol University of Technology, Babol, Iran Hedayati, H
Abstract :
We consider the fundamental relation ???? on a semihypergroup ?? to interpret the lower and upper approximations
as subsets of the fundamental semigroup ??/???? and we give some results in this connection. Also, we introduce the
notion of a bi-hyperideal to study the relationship between approximations and bi-hyperideals.
