Partial orders on semigroups of partial transformations with restricted range
Let X be any set and P(X) the set of all partial transformations defined on X, that is, all functions α:A→B where A,B are subsets of X. Then P(X) is a semigroup under composition. Let Y be a subset of X. Recently, Fernandes and Sanwong defined PT(X,Y)={α P(X):XαY } and defined I(X,Y) to be the set o...
Saved in:
Main Authors: | , |
---|---|
Format: | Article |
Language: | English |
Published: |
2014
|
Online Access: | http://www.scopus.com/inward/record.url?eid=2-s2.0-84864870168&partnerID=40&md5=40abf6b4a2588b4068d282144e2bffe4 http://cmuir.cmu.ac.th/handle/6653943832/6743 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Institution: | Chiang Mai University |
Language: | English |
Summary: | Let X be any set and P(X) the set of all partial transformations defined on X, that is, all functions α:A→B where A,B are subsets of X. Then P(X) is a semigroup under composition. Let Y be a subset of X. Recently, Fernandes and Sanwong defined PT(X,Y)={α P(X):XαY } and defined I(X,Y) to be the set of all injective transformations in PT(X,Y). Hence PT(X,Y) and I(X,Y) are subsemigroups of P(X). In this paper, we study properties of the so-called natural partial order ≥ on PT(X,Y) and I(X,Y) in terms of domains, images and kernels, compare ≥ with the subset order, characterise the meet and join of these two orders, then find elements of PT(X,Y) and I(X,Y) which are compatible. Also, the minimal and maximal elements are described. © 2012 Australian Mathematical Publishing Association Inc. |
---|