We study the problem of learning regular tree languages from text. We show that the framework of function distinguishability as introduced by the author in Theoretical Computer Science, 290:1679–1711, 2003, can be generalized from the case of string languages towards tree languages. This provides a large source of identifiable classes of regular tree languages. Each of these classes can be char...

In this paper, the concept of a fuzzy graph structure is introduced based on the concept of graph structure given by E. Sampathkumar, in Bull. Kerala Math. Assoc., Vol 3, No.2 (2006 December), 65123. New concepts like ρi − edge, ρi − path, ρi − cycle, ρi − tree, ρi − forest, fuzzy ρi − cycle, fuzzy ρi − tree, fuzzy ρi − forest etc. are introduced. Some results are obtained. We continue the stud...

A fuzzy decision tree is an important tool for knowledge acquisition in uncertain environments. Most of the existing fuzzy decision tree algorithms do not systematically consider the impact of the non-linear characteristics of the membership degree of fuzzy sets; they are therefore unable to integrate uncertainty processing preferences into the selection of extended attributes. This paper initi...